[examples/language-modeling] Add dataset download instructions

Had to hunt for instructions to get the dataset used in this set of examples, so this PR proposes to add them to README.md.

@patrickvonplaten

.circleci/config.yml

@@ -3,28 +3,6 @@ orbs:
     gcp-gke: circleci/gcp-gke@1.0.4
     go: circleci/go@1.3.0
 
-commands:
-  skip-job-on-doc-only-changes:
-    description: "Do not continue this job and exit with success for PRs with only doc changes"
-    steps:
-
-      - run:
-          name: docs-only changes skip check
-          command: |
-            # pipeline.git.base_revision is not always defined, so only proceed if all external vars are defined
-            if test -n "<< pipeline.git.base_revision >>" && test -n "<< pipeline.git.revision >>" && test -n "$(git diff --name-only << pipeline.git.base_revision >>...<< pipeline.git.revision >>)"
-            then
-                if git diff --name-only << pipeline.git.base_revision >>...<< pipeline.git.revision >> | egrep -qv '\.(md|rst)$'
-                then
-                    echo "Non-docs were modified in this PR, proceeding normally"
-                else
-                    echo "Only docs were modified in this PR, quitting this job"
-                    # disable skipping for now, as circleCI's base_revision is inconsistent leading to invalid ranges
-                    # circleci step halt
-                fi
-            else
-                echo "Can't perform skipping check w/o base_revision defined, continuing the job"
-            fi
 
 # TPU REFERENCES
 references:
@@ -95,13 +73,13 @@ jobs:
         parallelism: 1
         steps:
             - checkout
-            - skip-job-on-doc-only-changes
             - restore_cache:
                   keys:
                       - v0.4-torch_and_tf-{{ checksum "setup.py" }}
                       - v0.4-{{ checksum "setup.py" }}
             - run: pip install --upgrade pip
             - run: pip install .[sklearn,tf-cpu,torch,testing,sentencepiece]
+            - run: pip install tapas torch-scatter -f https://pytorch-geometric.com/whl/torch-1.7.0+cpu.html
             - save_cache:
                 key: v0.4-{{ checksum "setup.py" }}
                 paths:
@@ -122,13 +100,13 @@ jobs:
         parallelism: 1
         steps:
             - checkout
-            - skip-job-on-doc-only-changes
             - restore_cache:
                   keys:
                       - v0.4-torch-{{ checksum "setup.py" }}
                       - v0.4-{{ checksum "setup.py" }}
             - run: pip install --upgrade pip
             - run: pip install .[sklearn,torch,testing,sentencepiece]
+            - run: pip install tapas torch-scatter -f https://pytorch-geometric.com/whl/torch-1.7.0+cpu.html
             - save_cache:
                   key: v0.4-torch-{{ checksum "setup.py" }}
                   paths:
@@ -149,7 +127,6 @@ jobs:
         parallelism: 1
         steps:
             - checkout
-            - skip-job-on-doc-only-changes
             - restore_cache:
                   keys:
                       - v0.4-tf-{{ checksum "setup.py" }}
@@ -176,7 +153,6 @@ jobs:
         parallelism: 1
         steps:
             - checkout
-            - skip-job-on-doc-only-changes
             - restore_cache:
                 keys:
                     - v0.4-flax-{{ checksum "setup.py" }}
@@ -203,13 +179,13 @@ jobs:
         parallelism: 1
         steps:
             - checkout
-            - skip-job-on-doc-only-changes
             - restore_cache:
                   keys:
                       - v0.4-torch-{{ checksum "setup.py" }}
                       - v0.4-{{ checksum "setup.py" }}
             - run: pip install --upgrade pip
             - run: pip install .[sklearn,torch,testing,sentencepiece]
+            - run: pip install tapas torch-scatter -f https://pytorch-geometric.com/whl/torch-1.7.0+cpu.html
             - save_cache:
                   key: v0.4-torch-{{ checksum "setup.py" }}
                   paths:
@@ -230,7 +206,6 @@ jobs:
         parallelism: 1
         steps:
             - checkout
-            - skip-job-on-doc-only-changes
             - restore_cache:
                   keys:
                       - v0.4-tf-{{ checksum "setup.py" }}
@@ -255,7 +230,6 @@ jobs:
             RUN_CUSTOM_TOKENIZERS: yes
         steps:
             - checkout
-            - skip-job-on-doc-only-changes
             - restore_cache:
                   keys:
                       - v0.4-custom_tokenizers-{{ checksum "setup.py" }}
@@ -283,14 +257,13 @@ jobs:
         parallelism: 1
         steps:
             - checkout
-            - skip-job-on-doc-only-changes
             - restore_cache:
                   keys:
                       - v0.4-torch_examples-{{ checksum "setup.py" }}
                       - v0.4-{{ checksum "setup.py" }}
             - run: pip install --upgrade pip
             - run: pip install .[sklearn,torch,sentencepiece,testing]
-            - run: pip install -r examples/requirements.txt
+            - run: pip install -r examples/_tests_requirements.txt
             - save_cache:
                   key: v0.4-torch_examples-{{ checksum "setup.py" }}
                   paths:

.circleci/deploy.sh

@@ -53,4 +53,5 @@ deploy_doc "3ebb1b3" v3.2.0
 deploy_doc "0613f05" v3.3.1
 deploy_doc "eb0e0ce" v3.4.0
 deploy_doc "818878d" v3.5.1
-deploy_doc "c781171" # v4.0.0 Latest stable release
+deploy_doc "c781171" v4.0.0
+deploy_doc "bfa4ccf" # v4.1.1 Latest stable release

.github/workflows/model-templates.yml

@@ -0,0 +1,67 @@
+name: Model templates runner
+
+on:
+  push:
+    paths:
+      - "src/**"
+      - "tests/**"
+      - ".github/**"
+      - "templates/**"
+
+jobs:
+  run_tests_templates:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v1
+
+      - name: Install Python
+        uses: actions/setup-python@v1
+        with:
+          python-version: 3.6
+
+      - name: Loading cache.
+        uses: actions/cache@v2
+        id: cache
+        with:
+          path: ~/.cache/pip
+          key: v1.2-tests_templates
+          restore-keys: |
+            v1.2-tests_templates-${{ hashFiles('setup.py') }}
+            v1.2-tests_templates
+
+      - name: Install dependencies
+        run: |
+          pip install --upgrade pip
+          pip install .[dev]
+      - name: Create model files
+        run: |
+          transformers-cli add-new-model --testing --testing_file=templates/adding_a_new_model/tests/encoder-bert-tokenizer.json --path=templates/adding_a_new_model
+          transformers-cli add-new-model --testing --testing_file=templates/adding_a_new_model/tests/pt-encoder-bert-tokenizer.json --path=templates/adding_a_new_model
+          transformers-cli add-new-model --testing --testing_file=templates/adding_a_new_model/tests/standalone.json --path=templates/adding_a_new_model
+          transformers-cli add-new-model --testing --testing_file=templates/adding_a_new_model/tests/tf-encoder-bert-tokenizer.json --path=templates/adding_a_new_model
+          transformers-cli add-new-model --testing --testing_file=templates/adding_a_new_model/tests/tf-seq-2-seq-bart-tokenizer.json --path=templates/adding_a_new_model
+          transformers-cli add-new-model --testing --testing_file=templates/adding_a_new_model/tests/pt-seq-2-seq-bart-tokenizer.json --path=templates/adding_a_new_model
+          make style
+          python utils/check_table.py --fix_and_overwrite
+          python utils/check_dummies.py --fix_and_overwrite
+
+      - name: Run all non-slow tests
+        run: |
+          python -m pytest -n 2 --dist=loadfile -s --make-reports=tests_templates tests/*template*
+
+      - name: Run style changes
+        run: |
+          git fetch origin master:master
+          make fixup
+
+      - name: Failure short reports
+        if: ${{ always() }}
+        run: cat reports/tests_templates_failures_short.txt
+
+      - name: Test suite reports artifacts
+        if: ${{ always() }}
+        uses: actions/upload-artifact@v2
+        with:
+          name: run_all_tests_templates_test_reports
+          path: reports

.github/workflows/self-push.yml

@@ -50,6 +50,7 @@ jobs:
           pip install --upgrade pip
           pip install .[torch,sklearn,testing,onnxruntime,sentencepiece]
           pip install git+https://github.com/huggingface/datasets
+          pip install pandas torch-scatter -f https://pytorch-geometric.com/whl/torch-1.7.0+cu102.html
 
       - name: Are GPUs recognized by our DL frameworks
         run: |
@@ -187,6 +188,7 @@ jobs:
           pip install --upgrade pip
           pip install .[torch,sklearn,testing,onnxruntime,sentencepiece]
           pip install git+https://github.com/huggingface/datasets
+          pip install pandas torch-scatter -f https://pytorch-geometric.com/whl/torch-1.7.0+cu102.html
 
       - name: Are GPUs recognized by our DL frameworks
         run: |

.gitignore

@@ -159,3 +159,6 @@ tags
 
 # pre-commit
 .pre-commit*
+
+# .lock
+*.lock

README.md

@@ -213,6 +213,7 @@ Min, Patrick Lewis, Ledell Wu, Sergey Edunov, Danqi Chen, and Wen-tau Yih.
 1. **[LXMERT](https://huggingface.co/transformers/model_doc/lxmert.html)** (from UNC Chapel Hill) released with the paper [LXMERT: Learning Cross-Modality Encoder Representations from Transformers for Open-Domain Question Answering](https://arxiv.org/abs/1908.07490) by Hao Tan and Mohit Bansal.
 1. **[MarianMT](https://huggingface.co/transformers/model_doc/marian.html)** Machine translation models trained using [OPUS](http://opus.nlpl.eu/) data by Jörg Tiedemann. The [Marian Framework](https://marian-nmt.github.io/) is being developed by the Microsoft Translator Team.
 1. **[MBart](https://huggingface.co/transformers/model_doc/mbart.html)** (from Facebook) released with the paper [Multilingual Denoising Pre-training for Neural Machine Translation](https://arxiv.org/abs/2001.08210) by Yinhan Liu, Jiatao Gu, Naman Goyal, Xian Li, Sergey Edunov, Marjan Ghazvininejad, Mike Lewis, Luke Zettlemoyer.
+1. **[MPNet](https://huggingface.co/transformers/model_doc/mpnet.html)** (from Microsoft Research) released with the paper [MPNet: Masked and Permuted Pre-training for Language Understanding](https://arxiv.org/abs/2004.09297) by Kaitao Song, Xu Tan, Tao Qin, Jianfeng Lu, Tie-Yan Liu.
 1. **[MT5](https://huggingface.co/transformers/model_doc/mt5.html)** (from Google AI) released with the paper [mT5: A massively multilingual pre-trained text-to-text transformer](https://arxiv.org/abs/2010.11934) by Linting Xue, Noah Constant, Adam Roberts, Mihir Kale, Rami Al-Rfou, Aditya Siddhant, Aditya Barua, Colin Raffel.
 1. **[Pegasus](https://huggingface.co/transformers/model_doc/pegasus.html)** (from Google) released with the paper [PEGASUS: Pre-training with Extracted Gap-sentences for Abstractive Summarization](https://arxiv.org/abs/1912.08777)> by Jingqing Zhang, Yao Zhao, Mohammad Saleh and Peter J. Liu.
 1. **[ProphetNet](https://huggingface.co/transformers/model_doc/prophetnet.html)** (from Microsoft Research) released with the paper [ProphetNet: Predicting Future N-gram for Sequence-to-Sequence Pre-training](https://arxiv.org/abs/2001.04063) by Yu Yan, Weizhen Qi, Yeyun Gong, Dayiheng Liu, Nan Duan, Jiusheng Chen, Ruofei Zhang and Ming Zhou.
@@ -221,7 +222,7 @@ Min, Patrick Lewis, Ledell Wu, Sergey Edunov, Danqi Chen, and Wen-tau Yih.
 ultilingual BERT into [DistilmBERT](https://github.com/huggingface/transformers/tree/master/examples/distillation) and a German version of DistilBERT.
 1. **[SqueezeBert](https://huggingface.co/transformers/model_doc/squeezebert.html)** released with the paper [SqueezeBERT: What can computer vision teach NLP about efficient neural networks?](https://arxiv.org/abs/2006.11316) by Forrest N. Iandola, Albert E. Shaw, Ravi Krishna, and Kurt W. Keutzer.
 1. **[T5](https://huggingface.co/transformers/model_doc/t5.html)** (from Google AI) released with the paper [Exploring the Limits of Transfer Learning with a Unified Text-to-Text Transformer](https://arxiv.org/abs/1910.10683) by Colin Raffel and Noam Shazeer and Adam Roberts and Katherine Lee and Sharan Narang and Michael Matena and Yanqi Zhou and Wei Li and Peter J. Liu.
-1. **[TAPAS](https://huggingface.co/transformers/master/model_doc/tapas.html)** released with the paper [TAPAS: Weakly Supervised Table Parsing via Pre-training](https://arxiv.org/abs/2004.02349) by Jonathan Herzig, Paweł Krzysztof Nowak, Thomas Müller, Francesco Piccinno and Julian Martin Eisenschlos.
+1. **[TAPAS](https://huggingface.co/transformers/master/model_doc/tapas.html)** (from Google AI) released with the paper [TAPAS: Weakly Supervised Table Parsing via Pre-training](https://arxiv.org/abs/2004.02349) by Jonathan Herzig, Paweł Krzysztof Nowak, Thomas Müller, Francesco Piccinno and Julian Martin Eisenschlos.
 1. **[Transformer-XL](https://huggingface.co/transformers/model_doc/transformerxl.html)** (from Google/CMU) released with the paper [Transformer-XL: Attentive Language Models Beyond a Fixed-Length Context](https://arxiv.org/abs/1901.02860) by Zihang Dai*, Zhilin Yang*, Yiming Yang, Jaime Carbonell, Quoc V. Le, Ruslan Salakhutdinov.
 1. **[XLM](https://huggingface.co/transformers/model_doc/xlm.html)** (from Facebook) released together with the paper [Cross-lingual Language Model Pretraining](https://arxiv.org/abs/1901.07291) by Guillaume Lample and Alexis Conneau.
 1. **[XLM-ProphetNet](https://huggingface.co/transformers/model_doc/xlmprophetnet.html)** (from Microsoft Research) released with the paper [ProphetNet: Predicting Future N-gram for Sequence-to-Sequence Pre-training](https://arxiv.org/abs/2001.04063) by Yu Yan, Weizhen Qi, Yeyun Gong, Dayiheng Liu, Nan Duan, Jiusheng Chen, Ruofei Zhang and Ming Zhou.

docs/source/_static/js/custom.js

@@ -1,10 +1,11 @@
 // These two things need to be updated at each release for the version selector.
 // Last stable version
-const stableVersion = "v4.0.0"
-// Dictionary doc folder to label
+const stableVersion = "v4.1.1"
+// Dictionary doc folder to label. The last stable version should have an empty key.
 const versionMapping = {
     "master": "master",
-    "v4.0.0": "v4.0.0",
+    "": "v4.1.1 (stable)",
+    "v4.0.1": "v4.0.0/v4.0.1",
     "v3.5.1": "v3.5.0/v3.5.1",
     "v3.4.0": "v3.4.0",
     "v3.3.1": "v3.3.0/v3.3.1",

docs/source/bertology.rst

@@ -34,5 +34,5 @@ help people access the inner representations, mainly adapted from the great work
   in https://arxiv.org/abs/1905.10650.
 
 To help you understand and use these features, we have added a specific example script: `bertology.py
-<https://github.com/huggingface/transformers/blob/master/examples/bertology/run_bertology.py>`_ while extract
-information and prune a model pre-trained on GLUE.
+<https://github.com/huggingface/transformers/blob/master/examples/research_projects/bertology/run_bertology.py>`_ while
+extract information and prune a model pre-trained on GLUE.

docs/source/conf.py

@@ -26,7 +26,7 @@ author = u'huggingface'
 # The short X.Y version
 version = u''
 # The full version, including alpha/beta/rc tags
-release = u'4.0.0'
+release = u'4.1.1'
 
 
 # -- General configuration ---------------------------------------------------

docs/source/glossary.rst

@@ -226,7 +226,7 @@ Contrary to RNNs that have the position of each token embedded within them, tran
 each token. Therefore, the position IDs (``position_ids``) are used by the model to identify each token's position in
 the list of tokens.
 
-They are an optional parameter. If no ``position_ids`` is passed to the model, the IDs are automatically created as
+They are an optional parameter. If no ``position_ids`` are passed to the model, the IDs are automatically created as
 absolute positional embeddings.
 
 Absolute positional embeddings are selected in the range ``[0, config.max_position_embeddings - 1]``. Some models use

docs/source/index.rst

@@ -151,44 +151,47 @@ and conversion utilities for the following models:
 22. :doc:`MBart <model_doc/mbart>` (from Facebook) released with the paper `Multilingual Denoising Pre-training for
     Neural Machine Translation <https://arxiv.org/abs/2001.08210>`__ by Yinhan Liu, Jiatao Gu, Naman Goyal, Xian Li,
     Sergey Edunov, Marjan Ghazvininejad, Mike Lewis, Luke Zettlemoyer.
-23. :doc:`MT5 <model_doc/mt5>` (from Google AI) released with the paper `mT5: A massively multilingual pre-trained
+23. :doc:`MPNet <model_doc/mpnet>` (from Microsoft Research) released with the paper `MPNet: Masked and Permuted
+    Pre-training for Language Understanding <https://arxiv.org/abs/2004.09297>`__ by Kaitao Song, Xu Tan, Tao Qin,
+    Jianfeng Lu, Tie-Yan Liu.
+24. :doc:`MT5 <model_doc/mt5>` (from Google AI) released with the paper `mT5: A massively multilingual pre-trained
     text-to-text transformer <https://arxiv.org/abs/2010.11934>`__ by Linting Xue, Noah Constant, Adam Roberts, Mihir
     Kale, Rami Al-Rfou, Aditya Siddhant, Aditya Barua, Colin Raffel.
-24. :doc:`Pegasus <model_doc/pegasus>` (from Google) released with the paper `PEGASUS: Pre-training with Extracted
+25. :doc:`Pegasus <model_doc/pegasus>` (from Google) released with the paper `PEGASUS: Pre-training with Extracted
     Gap-sentences for Abstractive Summarization <https://arxiv.org/abs/1912.08777>`__> by Jingqing Zhang, Yao Zhao,
     Mohammad Saleh and Peter J. Liu.
-25. :doc:`ProphetNet <model_doc/prophetnet>` (from Microsoft Research) released with the paper `ProphetNet: Predicting
+26. :doc:`ProphetNet <model_doc/prophetnet>` (from Microsoft Research) released with the paper `ProphetNet: Predicting
     Future N-gram for Sequence-to-Sequence Pre-training <https://arxiv.org/abs/2001.04063>`__ by Yu Yan, Weizhen Qi,
     Yeyun Gong, Dayiheng Liu, Nan Duan, Jiusheng Chen, Ruofei Zhang and Ming Zhou.
-26. :doc:`Reformer <model_doc/reformer>` (from Google Research) released with the paper `Reformer: The Efficient
+27. :doc:`Reformer <model_doc/reformer>` (from Google Research) released with the paper `Reformer: The Efficient
     Transformer <https://arxiv.org/abs/2001.04451>`__ by Nikita Kitaev, Łukasz Kaiser, Anselm Levskaya.
-27. :doc:`RoBERTa <model_doc/roberta>` (from Facebook), released together with the paper a `Robustly Optimized BERT
+28. :doc:`RoBERTa <model_doc/roberta>` (from Facebook), released together with the paper a `Robustly Optimized BERT
     Pretraining Approach <https://arxiv.org/abs/1907.11692>`__ by Yinhan Liu, Myle Ott, Naman Goyal, Jingfei Du, Mandar
     Joshi, Danqi Chen, Omer Levy, Mike Lewis, Luke Zettlemoyer, Veselin Stoyanov. ultilingual BERT into `DistilmBERT
     <https://github.com/huggingface/transformers/tree/master/examples/distillation>`__ and a German version of
     DistilBERT.
-28. :doc:`SqueezeBert <model_doc/squeezebert>` released with the paper `SqueezeBERT: What can computer vision teach NLP
+29. :doc:`SqueezeBert <model_doc/squeezebert>` released with the paper `SqueezeBERT: What can computer vision teach NLP
     about efficient neural networks? <https://arxiv.org/abs/2006.11316>`__ by Forrest N. Iandola, Albert E. Shaw, Ravi
     Krishna, and Kurt W. Keutzer.
-29. :doc:`T5 <model_doc/t5>` (from Google AI) released with the paper `Exploring the Limits of Transfer Learning with a
+30. :doc:`T5 <model_doc/t5>` (from Google AI) released with the paper `Exploring the Limits of Transfer Learning with a
     Unified Text-to-Text Transformer <https://arxiv.org/abs/1910.10683>`__ by Colin Raffel and Noam Shazeer and Adam
     Roberts and Katherine Lee and Sharan Narang and Michael Matena and Yanqi Zhou and Wei Li and Peter J. Liu.
-30. :doc:`TAPAS <model_doc/tapas>` (from Google AI) released with the paper `TAPAS: Weakly Supervised Table Parsing via
-    Pre-training <https://arxiv.org/abs/2004.02349>`__ by Jonathan Herzig, Paweł Krzysztof Nowak, Thomas Müller,
-    Francesco Piccinno and Julian Martin Eisenschlos.
-31. :doc:`Transformer-XL <model_doc/transformerxl>` (from Google/CMU) released with the paper `Transformer-XL:
+31. `TAPAS <https://huggingface.co/transformers/master/model_doc/tapas.html>`__ (from Google AI) released with the
+    paper `TAPAS: Weakly Supervised Table Parsing via Pre-training <https://arxiv.org/abs/2004.02349>`__ by Jonathan
+    Herzig, Paweł Krzysztof Nowak, Thomas Müller, Francesco Piccinno and Julian Martin Eisenschlos.
+32. :doc:`Transformer-XL <model_doc/transformerxl>` (from Google/CMU) released with the paper `Transformer-XL:
     Attentive Language Models Beyond a Fixed-Length Context <https://arxiv.org/abs/1901.02860>`__ by Zihang Dai*,
     Zhilin Yang*, Yiming Yang, Jaime Carbonell, Quoc V. Le, Ruslan Salakhutdinov.
-32. :doc:`XLM <model_doc/xlm>` (from Facebook) released together with the paper `Cross-lingual Language Model
+33. :doc:`XLM <model_doc/xlm>` (from Facebook) released together with the paper `Cross-lingual Language Model
     Pretraining <https://arxiv.org/abs/1901.07291>`__ by Guillaume Lample and Alexis Conneau.
-33. :doc:`XLM-ProphetNet <model_doc/xlmprophetnet>` (from Microsoft Research) released with the paper `ProphetNet:
+34. :doc:`XLM-ProphetNet <model_doc/xlmprophetnet>` (from Microsoft Research) released with the paper `ProphetNet:
     Predicting Future N-gram for Sequence-to-Sequence Pre-training <https://arxiv.org/abs/2001.04063>`__ by Yu Yan,
     Weizhen Qi, Yeyun Gong, Dayiheng Liu, Nan Duan, Jiusheng Chen, Ruofei Zhang and Ming Zhou.
-34. :doc:`XLM-RoBERTa <model_doc/xlmroberta>` (from Facebook AI), released together with the paper `Unsupervised
+35. :doc:`XLM-RoBERTa <model_doc/xlmroberta>` (from Facebook AI), released together with the paper `Unsupervised
     Cross-lingual Representation Learning at Scale <https://arxiv.org/abs/1911.02116>`__ by Alexis Conneau*, Kartikay
     Khandelwal*, Naman Goyal, Vishrav Chaudhary, Guillaume Wenzek, Francisco Guzmán, Edouard Grave, Myle Ott, Luke
     Zettlemoyer and Veselin Stoyanov.
-35. :doc:`XLNet <model_doc/xlnet>` (from Google/CMU) released with the paper `​XLNet: Generalized Autoregressive
+36. :doc:`XLNet <model_doc/xlnet>` (from Google/CMU) released with the paper `​XLNet: Generalized Autoregressive
     Pretraining for Language Understanding <https://arxiv.org/abs/1906.08237>`__ by Zhilin Yang*, Zihang Dai*, Yiming
     Yang, Jaime Carbonell, Ruslan Salakhutdinov, Quoc V. Le.
 
@@ -243,6 +246,8 @@ TensorFlow and/or Flax.
 +-----------------------------+----------------+----------------+-----------------+--------------------+--------------+
 |         Longformer          |       ✅       |       ✅       |       ✅        |         ✅         |      ❌      |
 +-----------------------------+----------------+----------------+-----------------+--------------------+--------------+
+|            MPNet            |       ✅       |       ✅       |       ✅        |         ✅         |      ❌      |
++-----------------------------+----------------+----------------+-----------------+--------------------+--------------+
 |           Marian            |       ✅       |       ❌       |       ✅        |         ✅         |      ❌      |
 +-----------------------------+----------------+----------------+-----------------+--------------------+--------------+
 |         MobileBERT          |       ✅       |       ✅       |       ✅        |         ✅         |      ❌      |
@@ -267,6 +272,8 @@ TensorFlow and/or Flax.
 +-----------------------------+----------------+----------------+-----------------+--------------------+--------------+
 |             T5              |       ✅       |       ✅       |       ✅        |         ✅         |      ❌      |
 +-----------------------------+----------------+----------------+-----------------+--------------------+--------------+
+|            TAPAS            |       ✅       |       ❌       |       ✅        |         ❌         |      ❌      |
++-----------------------------+----------------+----------------+-----------------+--------------------+--------------+
 |       Transformer-XL        |       ✅       |       ❌       |       ✅        |         ✅         |      ❌      |
 +-----------------------------+----------------+----------------+-----------------+--------------------+--------------+
 |             XLM             |       ✅       |       ❌       |       ✅        |         ✅         |      ❌      |
@@ -282,7 +289,6 @@ TensorFlow and/or Flax.
 |             mT5             |       ✅       |       ✅       |       ✅        |         ✅         |      ❌      |
 +-----------------------------+----------------+----------------+-----------------+--------------------+--------------+
 
-
 .. toctree::
     :maxdepth: 2
     :caption: Get started
@@ -369,6 +375,7 @@ TensorFlow and/or Flax.
     model_doc/marian
     model_doc/mbart
     model_doc/mobilebert
+    model_doc/mpnet
     model_doc/mt5
     model_doc/gpt
     model_doc/gpt2

docs/source/internal/generation_utils.rst

@@ -15,7 +15,8 @@ Utilities for Generation
 
 This page lists all the utility functions used by :meth:`~transformers.PretrainedModel.generate`,
 :meth:`~transformers.PretrainedModel.greedy_search`, :meth:`~transformers.PretrainedModel.sample`,
-:meth:`~transformers.PretrainedModel.beam_search`, and :meth:`~transformers.PretrainedModel.beam_sample`.
+:meth:`~transformers.PretrainedModel.beam_search`, :meth:`~transformers.PretrainedModel.beam_sample`, and
+:meth:`~transformers.PretrainedModel.group_beam_search`.
 
 Most of those are only useful if you are studying the code of the generate methods in the library.
 
@@ -31,6 +32,9 @@ generation.
 .. autoclass:: transformers.LogitsProcessorList
     :members: __call__
 
+.. autoclass:: transformers.LogitsWarper
+    :members: __call__
+
 .. autoclass:: transformers.MinLengthLogitsProcessor
     :members: __call__
 
@@ -52,6 +56,12 @@ generation.
 .. autoclass:: transformers.NoBadWordsLogitsProcessor
     :members: __call__
 
+.. autoclass:: transformers.PrefixConstrainedLogitsProcessor
+    :members: __call__
+
+.. autoclass:: transformers.HammingDiversityLogitsProcessor
+    :members: __call__
+
 BeamSearch
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
@@ -60,3 +70,10 @@ BeamSearch
 
 .. autoclass:: transformers.BeamSearchScorer
     :members: process, finalize
+
+Utilities
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autofunction:: transformers.top_k_top_p_filtering
+
+.. autofunction:: transformers.tf_top_k_top_p_filtering

docs/source/internal/modeling_utils.rst

@@ -91,8 +91,6 @@ TensorFlow loss functions
 TensorFlow Helper Functions
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-.. autofunction:: transformers.modeling_tf_utils.cast_bool_to_primitive
-
 .. autofunction:: transformers.modeling_tf_utils.get_initializer
 
 .. autofunction:: transformers.modeling_tf_utils.keras_serializable

docs/source/internal/trainer_utils.rst

@@ -22,6 +22,8 @@ Utilities
 
 .. autoclass:: transformers.EvalPrediction
 
+.. autoclass:: transformers.EvaluationStrategy
+
 .. autofunction:: transformers.set_seed
 
 .. autofunction:: transformers.torch_distributed_zero_first
@@ -32,8 +34,15 @@ Callbacks internals
 
 .. autoclass:: transformers.trainer_callback.CallbackHandler
 
+
 Distributed Evaluation
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 .. autoclass:: transformers.trainer_pt_utils.DistributedTensorGatherer
     :members:
+
+
+Distributed Evaluation
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.HfArgumentParser

docs/source/main_classes/model.rst

@@ -13,9 +13,10 @@
 Models
 -----------------------------------------------------------------------------------------------------------------------
 
-The base classes :class:`~transformers.PreTrainedModel` and :class:`~transformers.TFPreTrainedModel` implement the
-common methods for loading/saving a model either from a local file or directory, or from a pretrained model
-configuration provided by the library (downloaded from HuggingFace's AWS S3 repository).
+The base classes :class:`~transformers.PreTrainedModel`, :class:`~transformers.TFPreTrainedModel`, and
+:class:`~transformers.FlaxPreTrainedModel` implement the common methods for loading/saving a model either from a local
+file or directory, or from a pretrained model configuration provided by the library (downloaded from HuggingFace's AWS
+S3 repository).
 
 :class:`~transformers.PreTrainedModel` and :class:`~transformers.TFPreTrainedModel` also implement a few methods which
 are common among all the models to:
@@ -57,6 +58,13 @@ TFModelUtilsMixin
     :members:
 
 
+FlaxPreTrainedModel
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.FlaxPreTrainedModel
+    :members:
+
+
 Generation
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

docs/source/main_classes/optimizer_schedules.rst

@@ -43,6 +43,10 @@ Schedules
 Learning Rate Schedules (Pytorch)
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
+.. autoclass:: transformers.SchedulerType
+
+.. autofunction:: transformers.get_scheduler
+
 .. autofunction:: transformers.get_constant_schedule
 
 
@@ -74,6 +78,10 @@ Learning Rate Schedules (Pytorch)
     :target: /imgs/warmup_linear_schedule.png
     :alt:
 
+
+.. autofunction:: transformers.get_polynomial_decay_schedule_with_warmup
+
+
 Warmup (TensorFlow)
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 

docs/source/main_classes/output.rst

@@ -126,13 +126,6 @@ CausalLMOutputWithCrossAttentions
     :members:
 
 
-CausalLMOutputWithPastAndCrossAttentions
-~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-
-.. autoclass:: transformers.modeling_outputs.CausalLMOutputWithPastAndCrossAttentions
-    :members:
-
-
 CausalLMOutputWithPast
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

docs/source/main_classes/pipelines.rst

@@ -34,6 +34,7 @@ There are two categories of pipeline abstractions to be aware about:
     - :class:`~transformers.TranslationPipeline`
     - :class:`~transformers.ZeroShotClassificationPipeline`
     - :class:`~transformers.Text2TextGenerationPipeline`
+    - :class:`~transformers.TableQuestionAnsweringPipeline`
 
 The pipeline abstraction
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -73,8 +74,9 @@ FillMaskPipeline
 NerPipeline
 =======================================================================================================================
 
-This class is an alias of the :class:`~transformers.TokenClassificationPipeline` defined below. Please refer to that
-pipeline for documentation and usage examples.
+.. autoclass:: transformers.NerPipeline
+
+See :class:`~transformers.TokenClassificationPipeline` for all details.
 
 QuestionAnsweringPipeline
 =======================================================================================================================
@@ -90,6 +92,13 @@ SummarizationPipeline
     :special-members: __call__
     :members:
 
+TableQuestionAnsweringPipeline
+=======================================================================================================================
+
+.. autoclass:: transformers.TableQuestionAnsweringPipeline
+    :special-members: __call__
+
+
 TextClassificationPipeline
 =======================================================================================================================
 
@@ -118,6 +127,13 @@ TokenClassificationPipeline
     :special-members: __call__
     :members:
 
+TranslationPipeline
+=======================================================================================================================
+
+.. autoclass:: transformers.TranslationPipeline
+    :special-members: __call__
+    :members:
+
 ZeroShotClassificationPipeline
 =======================================================================================================================
 

docs/source/main_classes/trainer.rst

@@ -63,6 +63,13 @@ Trainer
     :members:
 
 
+Seq2SeqTrainer
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.Seq2SeqTrainer
+    :members: evaluate, predict
+
+
 TFTrainer
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
@@ -77,6 +84,13 @@ TrainingArguments
     :members:
 
 
+Seq2SeqTrainingArguments
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.Seq2SeqTrainingArguments
+    :members:
+
+
 TFTrainingArguments
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

docs/source/model_doc/albert.rst

@@ -60,6 +60,13 @@ AlbertTokenizer
         create_token_type_ids_from_sequences, save_vocabulary
 
 
+AlbertTokenizerFast
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.AlbertTokenizerFast
+    :members:
+
+
 Albert specific outputs
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

docs/source/model_doc/auto.rst

@@ -114,6 +114,13 @@ AutoModelForQuestionAnswering
     :members:
 
 
+AutoModelForTableQuestionAnswering
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.AutoModelForTableQuestionAnswering
+    :members:
+
+
 TFAutoModel
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
@@ -175,3 +182,10 @@ TFAutoModelForQuestionAnswering
 
 .. autoclass:: transformers.TFAutoModelForQuestionAnswering
     :members:
+
+
+FlaxAutoModel
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.FlaxAutoModel
+    :members:

docs/source/model_doc/bart.rst

@@ -55,9 +55,8 @@ Implementation Notes
 
 - Bart doesn't use :obj:`token_type_ids` for sequence classification. Use :class:`~transformers.BartTokenizer` or
   :meth:`~transformers.BartTokenizer.encode` to get the proper splitting.
-- The forward pass of :class:`~transformers.BartModel` will create decoder inputs (using the helper function
-  :func:`transformers.models.bart.modeling_bart._prepare_bart_decoder_inputs`) if they are not passed. This is
-  different than some other modeling APIs.
+- The forward pass of :class:`~transformers.BartModel` will create the ``decoder_input_ids`` if they are not passed.
+  This is different than some other modeling APIs. A typical use case of this feature is mask filling.
 - Model predictions are intended to be identical to the original implementation when
   :obj:`force_bos_token_to_be_generated=True`. This only works, however, if the string you pass to
   :func:`fairseq.encode` starts with a space.
@@ -98,6 +97,12 @@ BartTokenizer
     :members:
 
 
+BartTokenizerFast
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.BartTokenizerFast
+    :members:
+
 
 BartModel
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -105,8 +110,6 @@ BartModel
 .. autoclass:: transformers.BartModel
     :members: forward
 
-.. autofunction:: transformers.models.bart.modeling_bart._prepare_bart_decoder_inputs
-
 
 BartForConditionalGeneration
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

docs/source/model_doc/barthez.rst

@@ -51,3 +51,9 @@ BarthezTokenizer
 .. autoclass:: transformers.BarthezTokenizer
     :members:
 
+
+BarthezTokenizerFast
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.BarthezTokenizerFast
+    :members:

docs/source/model_doc/bert.rst

@@ -207,3 +207,10 @@ FlaxBertModel
 
 .. autoclass:: transformers.FlaxBertModel
     :members: __call__
+
+
+FlaxBertForMaskedLM
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.FlaxBertForMaskedLM
+    :members: __call__

docs/source/model_doc/blenderbot.rst

@@ -100,6 +100,15 @@ BlenderbotSmallTokenizer
     :members:
 
 
+BlenderbotModel
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+See :obj:`transformers.BartModel` for arguments to `forward` and `generate`
+
+.. autoclass:: transformers.BlenderbotModel
+    :members:
+
+
 BlenderbotForConditionalGeneration
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

docs/source/model_doc/camembert.rst

@@ -54,6 +54,13 @@ CamembertTokenizer
         create_token_type_ids_from_sequences, save_vocabulary
 
 
+CamembertTokenizerFast
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.CamembertTokenizerFast
+    :members:
+
+
 CamembertModel
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

docs/source/model_doc/ctrl.rst

@@ -97,3 +97,8 @@ TFCTRLLMHeadModel
 .. autoclass:: transformers.TFCTRLLMHeadModel
     :members: call
 
+TFCTRLForSequenceClassification
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.TFCTRLForSequenceClassification
+    :members: call

docs/source/model_doc/gpt.rst

@@ -138,3 +138,9 @@ TFOpenAIGPTDoubleHeadsModel
 
 .. autoclass:: transformers.TFOpenAIGPTDoubleHeadsModel
     :members: call
+
+TFOpenAIGPTForSequenceClassification
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.TFOpenAIGPTForSequenceClassification
+    :members: call

docs/source/model_doc/layoutlm.rst

@@ -57,6 +57,13 @@ LayoutLMTokenizer
     :members:
 
 
+LayoutLMTokenizerFast
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.LayoutLMTokenizerFast
+    :members:
+
+
 LayoutLMModel
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

docs/source/model_doc/longformer.rst

@@ -34,6 +34,12 @@ contrast to most prior work, we also pretrain Longformer and finetune it on a va
 pretrained Longformer consistently outperforms RoBERTa on long document tasks and sets new state-of-the-art results on
 WikiHop and TriviaQA.*
 
+Tips:
+
+- Since the Longformer is based on RoBERTa, it doesn't have :obj:`token_type_ids`. You don't need to indicate which
+  token belongs to which segment. Just separate your segments with the separation token :obj:`tokenizer.sep_token` (or
+  :obj:`</s>`).
+
 The Authors' code can be found `here <https://github.com/allenai/longformer>`__.
 
 Longformer Self Attention

docs/source/model_doc/mbart.rst

@@ -90,6 +90,20 @@ MBartTokenizer
     :members: build_inputs_with_special_tokens, prepare_seq2seq_batch
 
 
+MBartTokenizerFast
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.MBartTokenizerFast
+    :members:
+
+
+MBartModel
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.MBartModel
+    :members:
+
+
 MBartForConditionalGeneration
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

docs/source/model_doc/mpnet.rst

@@ -0,0 +1,149 @@
+.. 
+    Copyright 2020 The HuggingFace Team. All rights reserved.
+
+    Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
+    the License. You may obtain a copy of the License at
+
+        http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
+    an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
+    specific language governing permissions and limitations under the License.
+
+MPNet
+-----------------------------------------------------------------------------------------------------------------------
+
+Overview
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The MPNet model was proposed in `MPNet: Masked and Permuted Pre-training for Language Understanding
+<https://arxiv.org/abs/2004.09297>`__ by Kaitao Song, Xu Tan, Tao Qin, Jianfeng Lu, Tie-Yan Liu.
+
+MPNet adopts a novel pre-training method, named masked and permuted language modeling, to inherit the advantages of
+masked language modeling and permuted language modeling for natural language understanding.
+
+The abstract from the paper is the following:
+
+*BERT adopts masked language modeling (MLM) for pre-training and is one of the most successful pre-training models.
+Since BERT neglects dependency among predicted tokens, XLNet introduces permuted language modeling (PLM) for
+pre-training to address this problem. However, XLNet does not leverage the full position information of a sentence and
+thus suffers from position discrepancy between pre-training and fine-tuning. In this paper, we propose MPNet, a novel
+pre-training method that inherits the advantages of BERT and XLNet and avoids their limitations. MPNet leverages the
+dependency among predicted tokens through permuted language modeling (vs. MLM in BERT), and takes auxiliary position
+information as input to make the model see a full sentence and thus reducing the position discrepancy (vs. PLM in
+XLNet). We pre-train MPNet on a large-scale dataset (over 160GB text corpora) and fine-tune on a variety of
+down-streaming tasks (GLUE, SQuAD, etc). Experimental results show that MPNet outperforms MLM and PLM by a large
+margin, and achieves better results on these tasks compared with previous state-of-the-art pre-trained methods (e.g.,
+BERT, XLNet, RoBERTa) under the same model setting.*
+
+Tips:
+
+- MPNet doesn't have :obj:`token_type_ids`, you don't need to indicate which token belongs to which segment. just
+  separate your segments with the separation token :obj:`tokenizer.sep_token` (or :obj:`[sep]`).
+
+The original code can be found `here <https://github.com/microsoft/MPNet>`__.
+
+MPNetConfig
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.MPNetConfig
+    :members:
+
+
+MPNetTokenizer
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.MPNetTokenizer
+    :members: build_inputs_with_special_tokens, get_special_tokens_mask,
+        create_token_type_ids_from_sequences, save_vocabulary
+
+
+MPNetTokenizerFast
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.MPNetTokenizerFast
+    :members:
+
+
+MPNetModel
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.MPNetModel
+    :members: forward
+
+
+MPNetForMaskedLM
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.MPNetForMaskedLM
+    :members: forward
+
+
+MPNetForSequenceClassification
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.MPNetForSequenceClassification
+    :members: forward
+
+
+MPNetForMultipleChoice
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.MPNetForMultipleChoice
+    :members: forward
+
+
+MPNetForTokenClassification
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.MPNetForTokenClassification
+    :members: forward
+
+
+MPNetForQuestionAnswering
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.MPNetForQuestionAnswering
+    :members: forward
+
+
+TFMPNetModel
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.TFMPNetModel
+    :members: call
+
+
+TFMPNetForMaskedLM
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.TFMPNetForMaskedLM
+    :members: call
+
+
+TFMPNetForSequenceClassification
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.TFMPNetForSequenceClassification
+    :members: call
+
+
+TFMPNetForMultipleChoice
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.TFMPNetForMultipleChoice
+    :members: call
+
+
+TFMPNetForTokenClassification
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.TFMPNetForTokenClassification
+    :members: call
+
+
+TFMPNetForQuestionAnswering
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.TFMPNetForQuestionAnswering
+    :members: call

docs/source/model_doc/mt5.rst

@@ -37,6 +37,22 @@ MT5Config
     :members:
 
 
+MT5Tokenizer
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.MT5Tokenizer
+
+See :class:`~transformers.T5Tokenizer` for all details.
+
+
+MT5TokenizerFast
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.MT5TokenizerFast
+
+See :class:`~transformers.T5TokenizerFast` for all details.
+
+
 MT5Model
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

docs/source/model_doc/pegasus.rst

@@ -112,6 +112,19 @@ warning: ``add_tokens`` does not work at the moment.
     :members: __call__, prepare_seq2seq_batch
 
 
+PegasusTokenizerFast
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.PegasusTokenizerFast
+    :members:
+
+
+PegasusModel
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.PegasusModel
+
+
 PegasusForConditionalGeneration
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

docs/source/model_doc/reformer.rst

@@ -163,6 +163,13 @@ ReformerTokenizer
     :members: save_vocabulary
 
 
+ReformerTokenizerFast
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.ReformerTokenizerFast
+    :members:
+
+
 ReformerModel
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

docs/source/model_doc/t5.rst

@@ -44,9 +44,9 @@ Tips:
 
   For more information about which prefix to use, it is easiest to look into Appendix D of the `paper
   <https://arxiv.org/pdf/1910.10683.pdf>`__. - For sequence-to-sequence generation, it is recommended to use
-  :obj:`T5ForConditionalGeneration.generate()``. This method takes care of feeding the encoded input via
-  cross-attention layers to the decoder and auto-regressively generates the decoder output. - T5 uses relative scalar
-  embeddings. Encoder input padding can be done on the left and on the right.
+  :obj:`T5ForConditionalGeneration.generate()`. This method takes care of feeding the encoded input via cross-attention
+  layers to the decoder and auto-regressively generates the decoder output. - T5 uses relative scalar embeddings.
+  Encoder input padding can be done on the left and on the right.
 
 The original code can be found `here <https://github.com/google-research/text-to-text-transfer-transformer>`__.
 
@@ -55,7 +55,7 @@ Training
 
 T5 is an encoder-decoder model and converts all NLP problems into a text-to-text format. It is trained using teacher
 forcing. This means that for training we always need an input sequence and a target sequence. The input sequence is fed
-to the model using :obj:`input_ids``. The target sequence is shifted to the right, i.e., prepended by a start-sequence
+to the model using :obj:`input_ids`. The target sequence is shifted to the right, i.e., prepended by a start-sequence
 token and fed to the decoder using the :obj:`decoder_input_ids`. In teacher-forcing style, the target sequence is then
 appended by the EOS token and corresponds to the :obj:`labels`. The PAD token is hereby used as the start-sequence
 token. T5 can be trained / fine-tuned both in a supervised and unsupervised fashion.
@@ -107,6 +107,13 @@ T5Tokenizer
         create_token_type_ids_from_sequences, prepare_seq2seq_batch, save_vocabulary
 
 
+T5TokenizerFast
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.T5TokenizerFast
+    :members:
+
+
 T5Model
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
@@ -124,7 +131,7 @@ T5EncoderModel
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 .. autoclass:: transformers.T5EncoderModel
-    :members: forward
+    :members: forward, parallelize, deparallelize
 
 TFT5Model
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

docs/source/model_doc/tapas.rst

@@ -1,19 +1,28 @@
 TAPAS
 -----------------------------------------------------------------------------------------------------------------------
 
+.. note::
+
+    This is a recently introduced model so the API hasn't been tested extensively. There may be some bugs or slight
+    breaking changes to fix them in the future.
+
+
+
 Overview
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 The TAPAS model was proposed in `TAPAS: Weakly Supervised Table Parsing via Pre-training
-<https://www.aclweb.org/anthology/2020.acl-main.398>`__ by Jonathan Herzig, Paweł Krzysztof Nowak, Thomas Müller, Francesco 
-Piccinno and Julian Martin Eisenschlos. It's a BERT-based model specifically designed (and pre-trained) for answering questions
-about tabular data. Compared to BERT, TAPAS uses relative position embeddings and has 7 token types that encode tabular
-structure. TAPAS is pre-trained on the masked language modeling (MLM) objective on a large dataset comprising millions
-of tables from English Wikipedia and corresponding texts. For question answering, TAPAS has 2 heads on top: a cell
-selection head and an aggregation head, for (optionally) performing aggregations (such as counting or summing) among
-selected cells. TAPAS has been fine-tuned on several datasets: SQA (Sequential Question Answering by Microsoft), WTQ
-(Wiki Table Questions by Stanford University) and WikiSQL (by Salesforce). It achieves state-of-the-art on both SQA and
-WTQ, while having comparable performance to SOTA on WikiSQL, with a much simpler architecture.
+<https://www.aclweb.org/anthology/2020.acl-main.398>`__ by Jonathan Herzig, Paweł Krzysztof Nowak, Thomas Müller,
+Francesco Piccinno and Julian Martin Eisenschlos. It's a BERT-based model specifically designed (and pre-trained) for
+answering questions about tabular data. Compared to BERT, TAPAS uses relative position embeddings and has 7 token types
+that encode tabular structure. TAPAS is pre-trained on the masked language modeling (MLM) objective on a large dataset
+comprising millions of tables from English Wikipedia and corresponding texts. For question answering, TAPAS has 2 heads
+on top: a cell selection head and an aggregation head, for (optionally) performing aggregations (such as counting or
+summing) among selected cells. TAPAS has been fine-tuned on several datasets: `SQA
+<https://www.microsoft.com/en-us/download/details.aspx?id=54253>`__ (Sequential Question Answering by Microsoft), `WTQ
+<https://github.com/ppasupat/WikiTableQuestions>`__ (Wiki Table Questions by Stanford University) and `WikiSQL
+<https://github.com/salesforce/WikiSQL>`__ (by Salesforce). It achieves state-of-the-art on both SQA and WTQ, while
+having comparable performance to SOTA on WikiSQL, with a much simpler architecture.
 
 The abstract from the paper is the following:
 
@@ -30,37 +39,38 @@ improving state-of-the-art accuracy on SQA from 55.1 to 67.2 and performing on p
 and WIKITQ, but with a simpler model architecture. We additionally find that transfer learning, which is trivial in our
 setting, from WIKISQL to WIKITQ, yields 48.7 accuracy, 4.2 points above the state-of-the-art.*
 
-In addition, the authors have further pre-trained TAPAS to recognize table entailment, by creating a balanced dataset
-of millions of automatically created training examples which are learned in an intermediate step prior to fine-tuning.
-The authors of TAPAS call this further pre-training intermediate pre-training (since TAPAS is first pre-trained on MLM,
-and then on another dataset). They found that intermediate pre-training further improves performance on SQA, achieving
-a new state-of-the-art as well as state-of-the-art on TabFact, a large-scale dataset with 16k Wikipedia tables for
-table entailment (a binary classification task). For more details, see their follow-up paper: `Understanding tables with
-intermediate pre-training <https://arxiv.org/abs/2010.00571>`__ by Julian Martin Eisenschlos, Syrine Krichene and
-Thomas Müller.
+In addition, the authors have further pre-trained TAPAS to recognize **table entailment**, by creating a balanced
+dataset of millions of automatically created training examples which are learned in an intermediate step prior to
+fine-tuning. The authors of TAPAS call this further pre-training intermediate pre-training (since TAPAS is first
+pre-trained on MLM, and then on another dataset). They found that intermediate pre-training further improves
+performance on SQA, achieving a new state-of-the-art as well as state-of-the-art on `TabFact
+<https://github.com/wenhuchen/Table-Fact-Checking>`__, a large-scale dataset with 16k Wikipedia tables for table
+entailment (a binary classification task). For more details, see their follow-up paper: `Understanding tables with
+intermediate pre-training <https://www.aclweb.org/anthology/2020.findings-emnlp.27/>`__ by Julian Martin Eisenschlos,
+Syrine Krichene and Thomas Müller.
 
-The original code can be found `here <https://github.com/google-research/tapas>`__. This page also includes links to the 
-datasets (SQA, WTQ, WikiSQL and TabFact).
+The original code can be found `here <https://github.com/google-research/tapas>`__.
 
 Tips:
 
 - TAPAS is a model that uses relative position embeddings by default (restarting the position embeddings at every cell
-  of the table). Note that this is something that was added after the publication of the original TAPAS paper. According 
-  to the authors, this usually results in a slightly better performance, and allows you to encode longer sequences without 
-  running out of embeddings. This is reflected in the ``reset_position_index_per_cell`` parameter of :class:`~transformers.TapasConfig`, 
-  which is set to ``True`` by default. 
-  The latest versions of the models available in the `model hub <https://huggingface.co/models?search=tapas>`_ all use relative 
-  position embeddings. You can still use the ones with absolute position embeddings by passing in a certain version when calling the
-  `.from_pretrained` method as explained in the model cards. 
-  Note that it's usually advised to pad the inputs on the right rather than the left.
-- TAPAS is based on BERT, so ``TAPAS-base`` for example corresponds to a ``BERT-base`` architecture. Of course, TAPAS-large 
-  will result in the best performance (the results reported in the paper are from TAPAS-large). Metrics of the various 
-  sized models are shown on the `original Github repository <https://github.com/google-research/tapas>`_. 
+  of the table). Note that this is something that was added after the publication of the original TAPAS paper.
+  According to the authors, this usually results in a slightly better performance, and allows you to encode longer
+  sequences without running out of embeddings. This is reflected in the ``reset_position_index_per_cell`` parameter of
+  :class:`~transformers.TapasConfig`, which is set to ``True`` by default. The default versions of the models available
+  in the `model hub <https://huggingface.co/models?search=tapas>`_ all use relative position embeddings. You can still
+  use the ones with absolute position embeddings by passing in an additional argument ``revision="no_reset"`` when
+  calling the ``.from_pretrained()`` method. Note that it's usually advised to pad the inputs on the right rather than
+  the left.
+- TAPAS is based on BERT, so ``TAPAS-base`` for example corresponds to a ``BERT-base`` architecture. Of course,
+  TAPAS-large will result in the best performance (the results reported in the paper are from TAPAS-large). Results of
+  the various sized models are shown on the `original Github repository <https://github.com/google-research/tapas>`_.
 - TAPAS has checkpoints fine-tuned on SQA, which are capable of answering questions related to a table in a
   conversational set-up. This means that you can ask follow-up questions such as "what is his age?" related to the
   previous question. Note that the forward pass of TAPAS is a bit different in case of a conversational set-up: in that
-  case, you have to feed every training example one by one to the model, such that the `prev_label_ids` token type ids
-  can be overwritten by the predicted `label_ids` of the model to the previous question. See "Usage" section for more info.
+  case, you have to feed every table-question pair one by one to the model, such that the `prev_labels` token type ids
+  can be overwritten by the predicted `labels` of the model to the previous question. See "Usage" section for more
+  info.
 - TAPAS is similar to BERT and therefore relies on the masked language modeling (MLM) objective. It is therefore
   efficient at predicting masked tokens and at NLU in general, but is not optimal for text generation. Models trained
   with a causal language modeling (CLM) objective are better in that regard.
@@ -69,30 +79,29 @@ Tips:
 Usage: fine-tuning
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-Here we explain how you can fine-tune :class:`~transformers.TapasForQuestionAnswering` on your own dataset. 
+Here we explain how you can fine-tune :class:`~transformers.TapasForQuestionAnswering` on your own dataset.
 
-===========================================================================
-STEP 1: Choose one of the 3 ways in which you can use TAPAS - or experiment
-===========================================================================
+**STEP 1: Choose one of the 3 ways in which you can use TAPAS - or experiment**
 
-Basically, there are 3 different ways in which one can fine-tune :class:`~transformers.TapasForQuestionAnswering`, corresponding to 
-the different datasets on which Tapas was fine-tuned:
+Basically, there are 3 different ways in which one can fine-tune :class:`~transformers.TapasForQuestionAnswering`,
+corresponding to the different datasets on which Tapas was fine-tuned:
 
-1. SQA: if you're interested in asking follow-up questions related to a table, in a conversational set-up. For example if you 
-   first ask "what's the name of the first actor?" then you can ask a follow-up question such as "how old is he?". Here, questions 
-   do not involve any aggregation (all questions are cell selection questions).
-2. WTQ: if you're not interested in asking questions in a conversational set-up, but rather just asking questions related 
-   to a table, which might involve aggregation, such as counting a number of rows, summing up cell values or averaging cell values. 
-   You can then for example ask "what's the total number of goals Cristiano Ronaldo made in his career?". This case is also called **weak 
-   supervision**, since the model itself must learn the appropriate aggregation operator (SUM/COUNT/AVERAGE/NONE) given only the answer 
-   to the question as supervision.
-3. WikiSQL-supervised: this dataset is based on WikiSQL with the model being given the ground truth aggregation operator during training. 
-   This is also called **strong supervision**. Here, learning the appropriate aggregation operator is much easier.
+1. SQA: if you're interested in asking follow-up questions related to a table, in a conversational set-up. For example
+   if you first ask "what's the name of the first actor?" then you can ask a follow-up question such as "how old is
+   he?". Here, questions do not involve any aggregation (all questions are cell selection questions).
+2. WTQ: if you're not interested in asking questions in a conversational set-up, but rather just asking questions
+   related to a table, which might involve aggregation, such as counting a number of rows, summing up cell values or
+   averaging cell values. You can then for example ask "what's the total number of goals Cristiano Ronaldo made in his
+   career?". This case is also called **weak supervision**, since the model itself must learn the appropriate
+   aggregation operator (SUM/COUNT/AVERAGE/NONE) given only the answer to the question as supervision.
+3. WikiSQL-supervised: this dataset is based on WikiSQL with the model being given the ground truth aggregation
+   operator during training. This is also called **strong supervision**. Here, learning the appropriate aggregation
+   operator is much easier.
 
 To summarize:
 
 +------------------------------------+----------------------+-------------------------------------------------------------------------------------------------------------------+
-| **Task**                           | **Example datasets** | **Description**                                                                                                   |
+| **Task**                           | **Example dataset**  | **Description**                                                                                                   |
 +------------------------------------+----------------------+-------------------------------------------------------------------------------------------------------------------+
 | Conversational                     | SQA                  | Conversational, only cell selection questions                                                                     |
 +------------------------------------+----------------------+-------------------------------------------------------------------------------------------------------------------+
@@ -101,20 +110,31 @@ To summarize:
 | Strong supervision for aggregation | WikiSQL-supervised   | Questions might involve aggregation, and the model must learn this given the gold aggregation operator            |
 +------------------------------------+----------------------+-------------------------------------------------------------------------------------------------------------------+
 
-Initializing a model with a pre-trained base and randomly initialized classification heads from the model hub is as easy as:
+Initializing a model with a pre-trained base and randomly initialized classification heads from the model hub can be
+done as follows (be sure to have installed the `torch-scatter dependency <https://github.com/rusty1s/pytorch_scatter>`_
+for your environment):
 
 .. code-block::
 
-        >>> from transformers import TapasForQuestionAnswering
+        >>> from transformers import TapasConfig, TapasForQuestionAnswering
 
-        >>> # for example, the base sized model 
-        >>> model = TapasForQuestionAnswering.from_pretrained('google/tapas-base-uncased')
+        >>> # for example, the base sized model with default SQA configuration
+        >>> model = TapasForQuestionAnswering.from_pretrained('google/tapas-base')
+
+        >>> # or, the base sized model with WTQ configuration
+        >>> config = TapasConfig.from_pretrained('google/tapas-base-finetuned-wtq')
+        >>> model = TapasForQuestionAnswering.from_pretrained('google/tapas-base', config=config)
+
+        >>> # or, the base sized model with WikiSQL configuration
+        >>> config = TapasConfig('google-base-finetuned-wikisql-supervised')
+        >>> model = TapasForQuestionAnswering.from_pretrained('google/tapas-base', config=config)
 
 
-Of course, you don't necessarily have to follow one of these three ways in which TAPAS was fine-tuned. You can also experiment by defining any hyperparameters 
-you want when initializing :class:`~transformers.TapasConfig`, and then create a :class:`~transformers.TapasForQuestionAnswering` based on that 
-configuration. For example, if you have a dataset that has both conversational questions and questions that might involve aggregation, then you can do it 
-this way. Here's an example:
+Of course, you don't necessarily have to follow one of these three ways in which TAPAS was fine-tuned. You can also
+experiment by defining any hyperparameters you want when initializing :class:`~transformers.TapasConfig`, and then
+create a :class:`~transformers.TapasForQuestionAnswering` based on that configuration. For example, if you have a
+dataset that has both conversational questions and questions that might involve aggregation, then you can do it this
+way. Here's an example:
 
 .. code-block::
 
@@ -123,81 +143,85 @@ this way. Here's an example:
         >>> # you can initialize the classification heads any way you want (see docs of TapasConfig)
         >>> config = TapasConfig(num_aggregation_labels=3, average_logits_per_cell=True, select_one_column=False)
         >>> # initializing the pre-trained base sized model with our custom classification heads
-        >>> model = TapasForQuestionAnswering.from_pretrained('google/tapas-base-uncased', config=config)
+        >>> model = TapasForQuestionAnswering.from_pretrained('google/tapas-base', config=config)
 
-What you can also do is start from an already fine-tuned checkpoint. A note here is that the already fine-tuned checkpoint on WTQ has some issues
-due to the L2-loss which is somewhat brittle. See `here <https://github.com/google-research/tapas/issues/91#issuecomment-735719340>`__ for more info.
+What you can also do is start from an already fine-tuned checkpoint. A note here is that the already fine-tuned
+checkpoint on WTQ has some issues due to the L2-loss which is somewhat brittle. See `here
+<https://github.com/google-research/tapas/issues/91#issuecomment-735719340>`__ for more info.
 
-For a list of all pre-trained and fine-tuned TAPAS checkpoints available in the HuggingFace model hub, see `here <https://huggingface.co/models?search=tapas>`__.
+For a list of all pre-trained and fine-tuned TAPAS checkpoints available in the HuggingFace model hub, see `here
+<https://huggingface.co/models?search=tapas>`__.
 
-===========================================
-STEP 2: Prepare your data in the SQA format
-===========================================
+**STEP 2: Prepare your data in the SQA format**
 
-Second, no matter what you picked above, you should prepare your dataset in the `SQA format <https://www.microsoft.com/en-us/download/details.aspx?id=54253>`__. 
-This format is a TSV/CSV file with the following columns:
+Second, no matter what you picked above, you should prepare your dataset in the `SQA format
+<https://www.microsoft.com/en-us/download/details.aspx?id=54253>`__. This format is a TSV/CSV file with the following
+columns:
 
-- ``id``: optional, id of the table-question pair, for bookkeeping purposes. 
-- ``annotator``: optional, id of the person who annotated the table-question pair, for bookkeeping purposes. 
-- ``position``: integer indicating if the question is the first, second, third,... related to the table. Only required in case of conversational setup (SQA). 
-  You don't need this column in case you're going for WTQ/WikiSQL-supervised.
+- ``id``: optional, id of the table-question pair, for bookkeeping purposes.
+- ``annotator``: optional, id of the person who annotated the table-question pair, for bookkeeping purposes.
+- ``position``: integer indicating if the question is the first, second, third,... related to the table. Only required
+  in case of conversational setup (SQA). You don't need this column in case you're going for WTQ/WikiSQL-supervised.
 - ``question``: string
 - ``table_file``: string, name of a csv file containing the tabular data
-- ``answer_coordinates``: list of one or more tuples (each tuple being a cell coordinate, i.e. row, column pair that is part of the answer)
+- ``answer_coordinates``: list of one or more tuples (each tuple being a cell coordinate, i.e. row, column pair that is
+  part of the answer)
 - ``answer_text``: list of one or more strings (each string being a cell value that is part of the answer)
-- ``aggregation_label``: index of the aggregation operator. Only required in case of strong supervision for aggregation (the WikiSQL-supervised case)
-- ``float_answer``: the float answer to the question, if there is one (np.nan if there isn't). Only required in case of weak supervision for aggregation (such as WTQ and WikiSQL)
+- ``aggregation_label``: index of the aggregation operator. Only required in case of strong supervision for aggregation
+  (the WikiSQL-supervised case)
+- ``float_answer``: the float answer to the question, if there is one (np.nan if there isn't). Only required in case of
+  weak supervision for aggregation (such as WTQ and WikiSQL)
 
-The tables themselves should be present in a folder, each table being a separate csv file. Note that the authors of the TAPAS algorithm used conversion 
-scripts with some automated logic to convert the other datasets (WTQ, WikiSQL) into the SQA format. The author explains this `here <https://github.com/google-research/tapas/issues/50#issuecomment-705465960>`__. 
-Interestingly, these conversion scripts are not perfect (the ``answer_coordinates`` and ``float_answer`` fields are populated based on the ``answer_text``), 
+The tables themselves should be present in a folder, each table being a separate csv file. Note that the authors of the
+TAPAS algorithm used conversion scripts with some automated logic to convert the other datasets (WTQ, WikiSQL) into the
+SQA format. The author explains this `here
+<https://github.com/google-research/tapas/issues/50#issuecomment-705465960>`__. Interestingly, these conversion scripts
+are not perfect (the ``answer_coordinates`` and ``float_answer`` fields are populated based on the ``answer_text``),
 meaning that WTQ and WikiSQL results could actually be improved.
 
+**STEP 3: Convert your data into PyTorch tensors using TapasTokenizer**
 
-==========================================================================================
-STEP 3: Convert your data into PyTorch tensors using :class:`~transformers.TapasTokenizer`
-==========================================================================================
-
-Third, given that you've prepared your data in this TSV/CSV format (and corresponding CSV files containing the tabular data), you can then 
-use :class:`~transformers.TapasTokenizer` to convert table-question pairs into :obj:`input_ids`, :obj:`attention_mask`, :obj:`token_type_ids`
-and so on. Again, based on which of the three cases you picked above, :class:`~transformers.TapasForQuestionAnswering` requires different inputs 
-to be fine-tuned:
+Third, given that you've prepared your data in this TSV/CSV format (and corresponding CSV files containing the tabular
+data), you can then use :class:`~transformers.TapasTokenizer` to convert table-question pairs into :obj:`input_ids`,
+:obj:`attention_mask`, :obj:`token_type_ids` and so on. Again, based on which of the three cases you picked above,
+:class:`~transformers.TapasForQuestionAnswering` requires different inputs to be fine-tuned:
 
 +------------------------------------+----------------------------------------------------------------------------------------------+
 | **Task**                           | **Required inputs**                                                                          |
 +------------------------------------+----------------------------------------------------------------------------------------------+
-| Conversational                     | ``input_ids``, ``attention_mask``, ``token_type_ids``, ``label_ids``                         |
+| Conversational                     | ``input_ids``, ``attention_mask``, ``token_type_ids``, ``labels``                            |
 +------------------------------------+----------------------------------------------------------------------------------------------+
-| Weak supervision for aggregation   | ``input_ids``, ``attention_mask``, ``token_type_ids``, ``label_ids``, ``numeric_values``,    |
+| Weak supervision for aggregation   | ``input_ids``, ``attention_mask``, ``token_type_ids``, ``labels``, ``numeric_values``,       |
 |                                    | ``numeric_values_scale``, ``float_answer``                                                   |
 +------------------------------------+----------------------------------------------------------------------------------------------+
-| Strong supervision for aggregation | ``input ids``, ``attention mask``, ``token type ids``, ``label ids``, ``aggregation_labels`` |
+| Strong supervision for aggregation | ``input ids``, ``attention mask``, ``token type ids``, ``labels``, ``aggregation_labels``    |
 +------------------------------------+----------------------------------------------------------------------------------------------+
 
-:class:`~transformers.TapasTokenizer` creates the ``label_ids``, ``numeric_values`` and ``numeric_values_scale`` based on the 
-``answer_coordinates`` and ``answer_text`` columns of the TSV file. The ``float_answer`` and ``aggregation_labels`` are already in the TSV file of step 2. 
-Here's an example:
+:class:`~transformers.TapasTokenizer` creates the ``labels``, ``numeric_values`` and ``numeric_values_scale`` based on
+the ``answer_coordinates`` and ``answer_text`` columns of the TSV file. The ``float_answer`` and ``aggregation_labels``
+are already in the TSV file of step 2. Here's an example:
 
 .. code-block::
 
         >>> from transformers import TapasTokenizer
         >>> import pandas as pd
 
-        >>> model_name = 'google/tapas-base-uncased'
+        >>> model_name = 'google/tapas-base'
         >>> tokenizer = TapasTokenizer.from_pretrained(model_name)
 
         >>> data = {'Actors': ["Brad Pitt", "Leonardo Di Caprio", "George Clooney"], 'Number of movies': ["87", "53", "69"]}
         >>> queries = ["What is the name of the first actor?", "How many movies has George Clooney played in?", "What is the total number of movies?"]
-        >>> answer_coordinates = [[(0, 0)], [(1, 0)], [(0, 2), (1, 2), (2, 2)]]
+        >>> answer_coordinates = [[(0, 0)], [(2, 1)], [(0, 1), (1, 1), (2, 1)]]
         >>> answer_text = [["Brad Pitt"], ["69"], ["209"]]
-        >>> table = pd.Dataframe(data)
+        >>> table = pd.DataFrame.from_dict(data)
         >>> inputs = tokenizer(table=table, queries=queries, answer_coordinates=answer_coordinates, answer_text=answer_text, padding='max_length', return_tensors='pt')
         >>> inputs
         {'input_ids': tensor([[ ... ]]), 'attention_mask': tensor([[...]]), 'token_type_ids': tensor([[[...]]]),
-        'numeric_values': tensor([[ ... ]]), 'numeric_values_scale: tensor([[ ... ]]), label_ids: tensor([[ ... ]])}
+        'numeric_values': tensor([[ ... ]]), 'numeric_values_scale: tensor([[ ... ]]), labels: tensor([[ ... ]])}
 
-Note that :class:`~transformers.TapasTokenizer` expects the data of the table to be text-only. You can use ``.astype(str)`` on a dataframe to turn it into
-text-only data. Of course, this only shows how to encode a single training example. It is advised to create a PyTorch dataset and a corresponding dataloader:
+Note that :class:`~transformers.TapasTokenizer` expects the data of the table to be **text-only**. You can use
+``.astype(str)`` on a dataframe to turn it into text-only data. Of course, this only shows how to encode a single
+training example. It is advised to create a PyTorch dataset and a corresponding dataloader:
 
 .. code-block::
 
@@ -214,15 +238,18 @@ text-only data. Of course, this only shows how to encode a single training examp
         ...
         ...     def __getitem__(self, idx):
         ...         item = data.iloc[idx]
-        ...         table = pd.read_csv(table_csv_path + item.table_file).astype(str)
+        ...         table = pd.read_csv(table_csv_path + item.table_file).astype(str) # be sure to make your table data text only
         ...         encoding = self.tokenizer(table=table, 
-        ...                                 queries=item.question, 
-        ...                                 answer_coordinates=item.answer_coordinates, 
-        ...                                 answer_text=item.answer_text,
-        ...                                 padding="max_length",
-        ...                                 return_tensors="pt"
+        ...                                   queries=item.question, 
+        ...                                   answer_coordinates=item.answer_coordinates, 
+        ...                                   answer_text=item.answer_text,
+        ...                                   truncation=True,
+        ...                                   padding="max_length",
+        ...                                   return_tensors="pt"
         ...         )
-        ...         # we add the float_answer which is also required (weak supervision for aggregation)
+        ...         # remove the batch dimension which the tokenizer adds by default
+        ...         encoding = {key: val.squeeze(0) for key, val in encoding.items()}
+        ...         # add the float_answer which is also required (weak supervision for aggregation case)
         ...         encoding["float_answer"] = torch.tensor(item.float_answer) 
         ...         return encoding
         ...
@@ -233,34 +260,56 @@ text-only data. Of course, this only shows how to encode a single training examp
         >>> train_dataset = TableDataset(data, tokenizer)
         >>> train_dataloader = torch.utils.data.DataLoader(train_dataset, batch_size=32)
 
-Note that here, we encode each table-question pair independently. This is fine as long as your dataset is **not conversational**. In case your 
-dataset involves conversational questions (such as in SQA), then you should first group together the ``queries``, ``answer_coordinates`` and 
-``answer_text`` per table (in the order of their ``position`` index) and batch encode each table with its questions. This will make sure that 
-the ``prev_label_ids`` token types (see docs of :class:`~transformers.TapasTokenizer`) are set correctly. 
+Note that here, we encode each table-question pair independently. This is fine as long as your dataset is **not
+conversational**. In case your dataset involves conversational questions (such as in SQA), then you should first group
+together the ``queries``, ``answer_coordinates`` and ``answer_text`` per table (in the order of their ``position``
+index) and batch encode each table with its questions. This will make sure that the ``prev_labels`` token types (see
+docs of :class:`~transformers.TapasTokenizer`) are set correctly. See `this notebook
+<https://github.com/NielsRogge/Transformers-Tutorials/blob/master/Fine_tuning_TapasForQuestionAnswering_on_SQA.ipynb>`__
+for more info.
 
-===================================================
-STEP 4: Train (fine-tune) TapasForQuestionAnswering
-===================================================
+**STEP 4: Train (fine-tune) TapasForQuestionAnswering**
 
-You can then fine-tune :class:`~transformers.TapasForQuestionAnswering` using native PyTorch as follows:
+You can then fine-tune :class:`~transformers.TapasForQuestionAnswering` using native PyTorch as follows (shown here for
+the weak supervision for aggregation case):
 
 .. code-block::
 
-        >>> from transformers import TapasForQuestionAnswering
+        >>> from transformers import TapasConfig, TapasForQuestionAnswering, AdamW
 
-        >>> model = TapasForQuestionAnswering.from_pretrained("google/tapas-base-uncased")
+        >>> # this is the default WTQ configuration
+        >>> config = TapasConfig(
+        ...            num_aggregation_labels = 4,
+        ...            use_answer_as_supervision = True,
+        ...            answer_loss_cutoff = 0.664694,
+        ...            cell_selection_preference = 0.207951,
+        ...            huber_loss_delta = 0.121194,
+        ...            init_cell_selection_weights_to_zero = True,
+        ...            select_one_column = True,
+        ...            allow_empty_column_selection = False,
+        ...            temperature = 0.0352513,
+        ... )
+        >>> model = TapasForQuestionAnswering.from_pretrained("google/tapas-base", config=config)
+
+        >>> optimizer = AdamW(model.parameters(), lr=5e-5)
 
         >>> for epoch in range(2):  # loop over the dataset multiple times
         ...    for idx, batch in enumerate(train_dataloader):
         ...         # get the inputs; 
-        ...         input_ids, attention_mask, token_type_ids, label_ids, numeric_values, numeric_values_scale, float_answer = batch
+        ...         input_ids = batch["input_ids"]
+        ...         attention_mask = batch["attention_mask"]
+        ...         token_type_ids = batch["token_type_ids"]
+        ...         labels = batch["labels"]
+        ...         numeric_values = batch["numeric_values"]
+        ...         numeric_values_scale = batch["numeric_values_scale"]
+        ...         float_answer = batch["float_answer"]
 
         ...         # zero the parameter gradients
         ...         optimizer.zero_grad()
 
         ...         # forward + backward + optimize
         ...         outputs = model(input_ids=input_ids, attention_mask=attention_mask, token_type_ids=token_type_ids, 
-        ...                        label_ids=label_ids, numeric_values=numeric_values, numeric_values_scale=numeric_values_scale, 
+        ...                        labels=labels, numeric_values=numeric_values, numeric_values_scale=numeric_values_scale, 
         ...                        float_answer=float_answer)
         ...         loss = outputs.loss
         ...         loss.backward()
@@ -269,34 +318,35 @@ You can then fine-tune :class:`~transformers.TapasForQuestionAnswering` using na
 Usage: inference
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-Here we explain how you can use :class:`~transformers.TapasForQuestionAnswering` for inference (i.e. making predictions on new data).
-For inference, only ``input_ids``, ``attention_mask`` and ``token_type_ids`` (which you can obtain using 
-:class:`~transformers.TapasTokenizer`) have to be provided to the model to obtain the logits. Next, you can use the handy 
-``convert_logits_to_predictions`` method of :class:`~transformers.TapasTokenizer` to convert these into predicted coordinates 
-and optional aggregation indices. 
+Here we explain how you can use :class:`~transformers.TapasForQuestionAnswering` for inference (i.e. making predictions
+on new data). For inference, only ``input_ids``, ``attention_mask`` and ``token_type_ids`` (which you can obtain using
+:class:`~transformers.TapasTokenizer`) have to be provided to the model to obtain the logits. Next, you can use the
+handy ``convert_logits_to_predictions`` method of :class:`~transformers.TapasTokenizer` to convert these into predicted
+coordinates and optional aggregation indices.
 
-However, note that inference is **different** depending on whether or not the setup is conversational. In a non-conversational set-up, inference 
-can be done in parallel on all table-question pairs of a batch. Here's an example of that:
+However, note that inference is **different** depending on whether or not the setup is conversational. In a
+non-conversational set-up, inference can be done in parallel on all table-question pairs of a batch. Here's an example
+of that:
 
 .. code-block::
 
         >>> from transformers import TapasTokenizer, TapasForQuestionAnswering
         >>> import pandas as pd 
 
-        >>> model_name = 'google/tapas-base-uncased-finetuned-wtq'
+        >>> model_name = 'google/tapas-base-finetuned-wtq'
         >>> model = TapasForQuestionAnswering.from_pretrained(model_name)
         >>> tokenizer = TapasTokenizer.from_pretrained(model_name)
 
         >>> data = {'Actors': ["Brad Pitt", "Leonardo Di Caprio", "George Clooney"], 'Number of movies': ["87", "53", "69"]}
         >>> queries = ["What is the name of the first actor?", "How many movies has George Clooney played in?", "What is the total number of movies?"]
-        >>> table = pd.Dataframe(data)
+        >>> table = pd.DataFrame.from_dict(data)
         >>> inputs = tokenizer(table=table, queries=queries, padding='max_length', return_tensors="pt") 
         >>> outputs = model(**inputs)
         >>> predicted_answer_coordinates, predicted_aggregation_indices = tokenizer.convert_logits_to_predictions(
         ...         inputs, 
-        ...         output.logits, 
-        ...         outputs.logits_aggregation
-        ...)
+        ...         outputs.logits.detach(), 
+        ...         outputs.logits_aggregation.detach()
+        ... )
 
         >>> # let's print out the results:
         >>> id2aggregation = {0: "NONE", 1: "SUM", 2: "AVERAGE", 3:"COUNT"}
@@ -306,15 +356,15 @@ can be done in parallel on all table-question pairs of a batch. Here's an exampl
         >>> for coordinates in predicted_answer_coordinates:
         ...   if len(coordinates) == 1:
         ...     # only a single cell:
-        ...     answers.append(df.iat[coordinates[0]])
+        ...     answers.append(table.iat[coordinates[0]])
         ...   else:
         ...     # multiple cells
         ...     cell_values = []
         ...     for coordinate in coordinates:
-        ...        cell_values.append(df.iat[coordinate])
+        ...        cell_values.append(table.iat[coordinate])
         ...     answers.append(", ".join(cell_values))
 
-        >>> display(df)
+        >>> display(table)
         >>> print("")
         >>> for query, answer, predicted_agg in zip(queries, answers, aggregation_predictions_string):
         ...   print(query)
@@ -322,15 +372,17 @@ can be done in parallel on all table-question pairs of a batch. Here's an exampl
         ...     print("Predicted answer: " + answer)
         ...   else:
         ...     print("Predicted answer: " + predicted_agg + " > " + answer)    
-        When was Brad Pitt born?
-        Predicted answer: 18 december 1963
-        Which actor appeared in the least number of movies?
-        Predicted answer: Leonardo Di Caprio
-        What is the average number of movies?
-        Predicted answer: AVERAGE > 87, 53, 69
+        What is the name of the first actor?
+        Predicted answer: Brad Pitt
+        How many movies has George Clooney played in?
+        Predicted answer: COUNT > 69
+        What is the total number of movies?
+        Predicted answer: SUM > 87, 53, 69
 
-In case of a conversational set-up, then each table-question pair must be provided **sequentially** to the model, such that
-the ``prev_label_ids`` token types can be overwritten by the predicted ``label_ids`` of the previous table-question pair. 
+In case of a conversational set-up, then each table-question pair must be provided **sequentially** to the model, such
+that the ``prev_labels`` token types can be overwritten by the predicted ``labels`` of the previous table-question
+pair. Again, more info can be found in `this notebook
+<https://github.com/NielsRogge/Transformers-Tutorials/blob/master/Fine_tuning_TapasForQuestionAnswering_on_SQA.ipynb>`__.
 
 
 Tapas specific outputs
@@ -358,14 +410,14 @@ TapasModel
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 .. autoclass:: transformers.TapasModel
-    :members:
+    :members: forward
 
 
 TapasForMaskedLM
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 .. autoclass:: transformers.TapasForMaskedLM
-    :members:
+    :members: forward
 
 
 TapasForSequenceClassification
@@ -379,4 +431,4 @@ TapasForQuestionAnswering
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 .. autoclass:: transformers.TapasForQuestionAnswering
-    :members:
+    :members: forward

docs/source/model_doc/transformerxl.rst

@@ -87,12 +87,14 @@ TransfoXLLMHeadModel
 .. autoclass:: transformers.TransfoXLLMHeadModel
     :members: forward
 
+
 TransfoXLForSequenceClassification
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 .. autoclass:: transformers.TransfoXLForSequenceClassification
     :members: forward
 
+
 TFTransfoXLModel
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
@@ -105,3 +107,18 @@ TFTransfoXLLMHeadModel
 
 .. autoclass:: transformers.TFTransfoXLLMHeadModel
     :members: call
+
+
+TFTransfoXLForSequenceClassification
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.TFTransfoXLForSequenceClassification
+    :members: call
+
+
+Internal Layers
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.AdaptiveEmbedding
+
+.. autoclass:: transformers.TFAdaptiveEmbedding

docs/source/model_doc/xlmroberta.rst

@@ -62,6 +62,13 @@ XLMRobertaTokenizer
         create_token_type_ids_from_sequences, save_vocabulary
 
 
+XLMRobertaTokenizerFast
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.XLMRobertaTokenizerFast
+    :members:
+
+
 XLMRobertaModel
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

docs/source/model_doc/xlnet.rst

@@ -62,6 +62,13 @@ XLNetTokenizer
         create_token_type_ids_from_sequences, save_vocabulary
 
 
+XLNetTokenizerFast
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+.. autoclass:: transformers.XLNetTokenizerFast
+    :members:
+
+
 XLNet specific outputs
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 

docs/source/model_sharing.rst

@@ -60,7 +60,7 @@ Basic steps
 In order to upload a model, you'll need to first create a git repo. This repo will live on the model hub, allowing
 users to clone it and you (and your organization members) to push to it.
 
-You can create a model repo directly from the website, `here <https://huggingface.co/new>`.
+You can create a model repo **directly from `the /new page on the website <https://huggingface.co/new>`__.**
 
 Alternatively, you can use the ``transformers-cli``. The next steps describe that process:
 
@@ -82,12 +82,12 @@ This creates a repo on the model hub, which can be cloned.
 
 .. code-block:: bash
 
-    git clone https://huggingface.co/username/your-model-name
-
     # Make sure you have git-lfs installed
     # (https://git-lfs.github.com/)
     git lfs install
 
+    git clone https://huggingface.co/username/your-model-name
+
 When you have your local clone of your repo and lfs installed, you can then add/remove from that clone as you would
 with any other git repo.
 
@@ -98,8 +98,12 @@ with any other git repo.
     echo "hello" >> README.md
     git add . && git commit -m "Update from $USER"
 
-We are intentionally not wrapping git too much, so as to stay intuitive and easy-to-use.
+We are intentionally not wrapping git too much, so that you can go on with the workflow you're used to and the tools
+you already know.
 
+The only learning curve you might have compared to regular git is the one for git-lfs. The documentation at
+`git-lfs.github.com <https://git-lfs.github.com/>`__ is decent, but we'll work on a tutorial with some tips and tricks
+in the coming weeks!
 
 Make your model work on all frameworks
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -110,7 +114,7 @@ Make your model work on all frameworks
 You probably have your favorite framework, but so will other users! That's why it's best to upload your model with both
 PyTorch `and` TensorFlow checkpoints to make it easier to use (if you skip this step, users will still be able to load
 your model in another framework, but it will be slower, as it will have to be converted on the fly). Don't worry, it's
-super easy to do (and in a future version, it will all be automatic). You will need to install both PyTorch and
+super easy to do (and in a future version, it might all be automatic). You will need to install both PyTorch and
 TensorFlow for this step, but you don't need to worry about the GPU, so it should be very easy. Check the `TensorFlow
 installation page <https://www.tensorflow.org/install/pip#tensorflow-2.0-rc-is-available>`__ and/or the `PyTorch
 installation page <https://pytorch.org/get-started/locally/#start-locally>`__ to see how.
@@ -192,7 +196,7 @@ status`` command:
     git add --all
     git status
 
-Finally, the files should be comitted:
+Finally, the files should be committed:
 
 .. code-block:: bash
 
@@ -210,23 +214,20 @@ This will upload the folder containing the weights, tokenizer and configuration
 Add a model card
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 
-To make sure everyone knows what your model can do, what its limitations and potential bias or ethetical
-considerations, please add a README.md model card to the 🤗 Transformers repo under `model_cards/`. It should then be
-placed in a subfolder with your username or organization, then another subfolder named like your model
-(`awesome-name-you-picked`). Or just click on the "Create a model card on GitHub" button on the model page, it will get
-you directly to the right location. If you need one, `here <https://github.com/huggingface/model_card>`__ is a model
-card template (meta-suggestions are welcome).
+To make sure everyone knows what your model can do, what its limitations, potential bias or ethical considerations are,
+please add a README.md model card to your model repo. You can just create it, or there's also a convenient button
+titled "Add a README.md" on your model page. A model card template can be found `here
+<https://github.com/huggingface/model_card>`__ (meta-suggestions are welcome). model card template (meta-suggestions
+are welcome).
+
+.. note::
+
+    Model cards used to live in the 🤗 Transformers repo under `model_cards/`, but for consistency and scalability we
+    migrated every model card from the repo to its corresponding huggingface.co model repo.
 
 If your model is fine-tuned from another model coming from the model hub (all 🤗 Transformers pretrained models do),
 don't forget to link to its model card so that people can fully trace how your model was built.
 
-If you have never made a pull request to the 🤗 Transformers repo, look at the :doc:`contributing guide <contributing>`
-to see the steps to follow.
-
-.. note::
-
-    You can also send your model card in the folder you uploaded with the CLI by placing it in a `README.md` file
-    inside `path/to/awesome-name-you-picked/`.
 
 Using your model
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -262,7 +263,8 @@ First you need to install `git-lfs` in the environment used by the notebook:
 
     sudo apt-get install git-lfs
 
-Then you can use the :obj:`transformers-cli` to create your new repo:
+Then you can use either create a repo directly from `huggingface.co <https://huggingface.co/>`__ , or use the
+:obj:`transformers-cli` to create it:
 
 
 .. code-block:: bash
@@ -274,13 +276,14 @@ Once it's created, you can clone it and configure it (replace username by your u
 
 .. code-block:: bash
 
+    git lfs install
+
     git clone https://username:password@huggingface.co/username/your-model-name
     # Alternatively if you have a token,
     # you can use it instead of your password
     git clone https://username:token@huggingface.co/username/your-model-name
 
     cd your-model-name
-    git lfs install
     git config --global user.email "email@example.com"
     # Tip: using the same email than for your huggingface.co account will link your commits to your profile
     git config --global user.name "Your name"

docs/source/model_summary.rst

@@ -16,7 +16,7 @@ Summary of the models
 This is a summary of the models available in 🤗 Transformers. It assumes you’re familiar with the original `transformer
 model <https://arxiv.org/abs/1706.03762>`_. For a gentle introduction check the `annotated transformer
 <http://nlp.seas.harvard.edu/2018/04/03/attention.html>`_. Here we focus on the high-level differences between the
-models. You can check them more in detail in their respective documentation. Also checkout the :doc:`pretrained model
+models. You can check them more in detail in their respective documentation. Also check out the :doc:`pretrained model
 page </pretrained_models>` to see the checkpoints available for each type of model and all `the community models
 <https://huggingface.co/models>`_.
 
@@ -30,7 +30,7 @@ Each one of the models in the library falls into one of the following categories
 
 Autoregressive models are pretrained on the classic language modeling task: guess the next token having read all the
 previous ones. They correspond to the decoder of the original transformer model, and a mask is used on top of the full
-sentence so that the attention heads can only see what was before in the next, and not what’s after. Although those
+sentence so that the attention heads can only see what was before in the text, and not what’s after. Although those
 models can be fine-tuned and achieve great results on many tasks, the most natural application is text generation. A
 typical example of such models is GPT.
 
@@ -512,8 +512,8 @@ BART
 <https://arxiv.org/abs/1910.13461>`_, Mike Lewis et al.
 
 Sequence-to-sequence model with an encoder and a decoder. Encoder is fed a corrupted version of the tokens, decoder is
-fed the original tokens (but has a mask to hide the future words like a regular transformers decoder). For the encoder
-, on the pretraining tasks, a composition of the following transformations are applied:
+fed the original tokens (but has a mask to hide the future words like a regular transformers decoder). A composition of
+the following transformations are applied on the pretraining tasks for the encoder:
 
   * mask random tokens (like in BERT)
   * delete random tokens

docs/source/philosophy.rst

@@ -78,7 +78,7 @@ The library is built around three types of classes for each model:
 All these classes can be instantiated from pretrained instances and saved locally using two methods:
 
 - :obj:`from_pretrained()` lets you instantiate a model/configuration/tokenizer from a pretrained version either
-  provided by the library itself (the supported models are provided in the list :doc:`here <pretrained_models>` or
+  provided by the library itself (the supported models are provided in the list :doc:`here <pretrained_models>`) or
   stored locally (or on a server) by the user,
 - :obj:`save_pretrained()` lets you save a model/configuration/tokenizer locally so that it can be reloaded using
   :obj:`from_pretrained()`.

docs/source/preprocessing.rst

@@ -10,17 +10,17 @@
     an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
     specific language governing permissions and limitations under the License.
 
-reprocessing data
+Preprocessing data
 =======================================================================================================================
 
 In this tutorial, we'll explore how to preprocess your data using 🤗 Transformers. The main tool for this is what we
 call a :doc:`tokenizer <main_classes/tokenizer>`. You can build one using the tokenizer class associated to the model
 you would like to use, or directly with the :class:`~transformers.AutoTokenizer` class.
 
-As we saw in the :doc:`quicktour </quicktour>`, the tokenizer will first split a given text in words (or part of words,
-punctuation symbols, etc.) usually called `tokens`. Then it will convert those `tokens` into numbers, to be able to
-build a tensor out of them and feed them to the model. It will also add any additional inputs the model might expect to
-work properly.
+As we saw in the :doc:`quick tour </quicktour>`, the tokenizer will first split a given text in words (or part of
+words, punctuation symbols, etc.) usually called `tokens`. Then it will convert those `tokens` into numbers, to be able
+to build a tensor out of them and feed them to the model. It will also add any additional inputs the model might expect
+to work properly.
 
 .. note::
 
@@ -131,7 +131,7 @@ ones it should not (because they represent padding in this case).
 
 
 Note that if your model does not have a maximum length associated to it, the command above will throw a warning. You
-can safely ignore it. You can also pass ``verbose=False`` to stop the tokenizer to throw those kinds of warnings.
+can safely ignore it. You can also pass ``verbose=False`` to stop the tokenizer from throwing those kinds of warnings.
 
 .. _sentence-pairs:
 
@@ -216,7 +216,6 @@ Everything you always wanted to know about padding and truncation
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
 We have seen the commands that will work for most cases (pad your batch to the length of the maximum sentence and
-
 truncate to the maximum length the mode can accept). However, the API supports more strategies if you need them. The
 three arguments you need to know for this are :obj:`padding`, :obj:`truncation` and :obj:`max_length`.
 

docs/source/quicktour.rst

@@ -158,7 +158,7 @@ Using the tokenizer
 
 We mentioned the tokenizer is responsible for the preprocessing of your texts. First, it will split a given text in
 words (or part of words, punctuation symbols, etc.) usually called `tokens`. There are multiple rules that can govern
-that process (you can learn more about them in the :doc:`tokenizer summary <tokenizer_summary>`, which is why we need
+that process (you can learn more about them in the :doc:`tokenizer summary <tokenizer_summary>`), which is why we need
 to instantiate the tokenizer using the name of the model, to make sure we use the same rules as when the model was
 pretrained.
 

docs/source/task_summary.rst

@@ -327,7 +327,7 @@ Masked Language Modeling
 Masked language modeling is the task of masking tokens in a sequence with a masking token, and prompting the model to
 fill that mask with an appropriate token. This allows the model to attend to both the right context (tokens on the
 right of the mask) and the left context (tokens on the left of the mask). Such a training creates a strong basis for
-downstream tasks, requiring bi-directional context such as SQuAD (question answering, see `Lewis, Lui, Goyal et al.
+downstream tasks requiring bi-directional context, such as SQuAD (question answering, see `Lewis, Lui, Goyal et al.
 <https://arxiv.org/abs/1910.13461>`__, part 4.2).
 
 Here is an example of using pipelines to replace a mask from a sequence:
@@ -657,7 +657,7 @@ Here are the expected results:
         {'word': 'Bridge', 'score': 0.990249514579773, 'entity': 'I-LOC'}
     ]
 
-Note, how the tokens of the sequence "Hugging Face" have been identified as an organisation, and "New York City",
+Note how the tokens of the sequence "Hugging Face" have been identified as an organisation, and "New York City",
 "DUMBO" and "Manhattan Bridge" have been identified as locations.
 
 Here is an example of doing named entity recognition, using a model and a tokenizer. The process is the following:

docs/source/testing.rst

@@ -1142,3 +1142,66 @@ To start a debugger at the point of the warning, do this:
 .. code-block:: bash
 
     pytest tests/test_logging.py -W error::UserWarning --pdb
+
+
+
+Testing Experimental CI Features
+-----------------------------------------------------------------------------------------------------------------------
+
+Testing CI features can be potentially problematic as it can interfere with the normal CI functioning. Therefore if a
+new CI feature is to be added, it should be done as following.
+
+1. Create a new dedicated job that tests what needs to be tested
+2. The new job must always succeed so that it gives us a green ✓ (details below).
+3. Let it run for some days to see that a variety of different PR types get to run on it (user fork branches,
+   non-forked branches, branches originating from github.com UI direct file edit, various forced pushes, etc. - there
+   are so many) while monitoring the experimental job's logs (not the overall job green as it's purposefully always
+   green)
+4. When it's clear that everything is solid, then merge the new changes into existing jobs.
+
+That way experiments on CI functionality itself won't interfere with the normal workflow.
+
+Now how can we make the job always succeed while the new CI feature is being developed?
+
+Some CIs, like TravisCI support ignore-step-failure and will report the overall job as successful, but CircleCI and
+Github Actions as of this writing don't support that.
+
+So the following workaround can be used:
+
+1. ``set +euo pipefail`` at the beginning of the run command to suppress most potential failures in the bash script.
+2. the last command must be a success: ``echo "done"`` or just ``true`` will do
+
+Here is an example:
+
+.. code-block:: yaml
+
+    - run:
+        name: run CI experiment
+        command: |
+            set +euo pipefail
+            echo "setting run-all-despite-any-errors-mode"
+            this_command_will_fail
+            echo "but bash continues to run"
+            # emulate another failure
+            false
+            # but the last command must be a success
+            echo "during experiment do not remove: reporting success to CI, even if there were failures"
+
+For simple commands you could also do:
+
+.. code-block:: bash
+
+    cmd_that_may_fail || true
+
+Of course, once satisfied with the results, integrate the experimental step or job with the rest of the normal jobs,
+while removing ``set +euo pipefail`` or any other things you may have added to ensure that the experimental job doesn't
+interfere with the normal CI functioning.
+
+This whole process would have been much easier if we only could set something like ``allow-failure`` for the
+experimental step, and let it fail without impacting the overall status of PRs. But as mentioned earlier CircleCI and
+Github Actions don't support it at the moment.
+
+You can vote for this feature and see where it is at at these CI-specific threads:
+
+* `Github Actions: <https://github.com/actions/toolkit/issues/399>`__
+* `CircleCI: <https://ideas.circleci.com/ideas/CCI-I-344>`__

docs/source/tokenizer_summary.rst

@@ -18,7 +18,7 @@ On this page, we will have a closer look at tokenization. As we saw in :doc:`the
 look-up table. Converting words or subwords to ids is straightforward, so in this summary, we will focus on splitting a
 text into words or subwords (i.e. tokenizing a text). More specifically, we will look at the three main types of
 tokenizers used in 🤗 Transformers: :ref:`Byte-Pair Encoding (BPE) <byte-pair-encoding>`, :ref:`WordPiece <wordpiece>`,
-and :ref:`SentencePiece <sentencepiece>`, and show exemplary which tokenizer type is used by which model.
+and :ref:`SentencePiece <sentencepiece>`, and show examples of which tokenizer type is used by which model.
 
 Note that on each model page, you can look at the documentation of the associated tokenizer to know which tokenizer
 type was used by the pretrained model. For instance, if we look at :class:`~transformers.BertTokenizer`, we can see
@@ -72,7 +72,7 @@ greater than 50,000, especially if they are pretrained only on a single language
 So if simple space and punctuation tokenization is unsatisfactory, why not simply tokenize on characters? While
 character tokenization is very simple and would greatly reduce memory and time complexity it makes it much harder for
 the model to learn meaningful input representations. *E.g.* learning a meaningful context-independent representation
-for the letter ``"t"`` is much harder as learning a context-independent representation for the word ``"today"``.
+for the letter ``"t"`` is much harder than learning a context-independent representation for the word ``"today"``.
 Therefore, character tokenization is often accompanied by a loss of performance. So to get the best of both worlds,
 transformers models use a hybrid between word-level and character-level tokenization called **subword** tokenization.
 
@@ -202,10 +202,10 @@ WordPiece
 
 WordPiece is the subword tokenization algorithm used for :doc:`BERT <model_doc/bert>`, :doc:`DistilBERT
 <model_doc/distilbert>`, and :doc:`Electra <model_doc/electra>`. The algorithm was outlined in `Japanese and Korean
-Voice Seach (Schuster et al., 2012)
+Voice Search (Schuster et al., 2012)
 <https://static.googleusercontent.com/media/research.google.com/ja//pubs/archive/37842.pdf>`__ and is very similar to
 BPE. WordPiece first initializes the vocabulary to include every character present in the training data and
-progressively learn a given number of merge rules. In contrast to BPE, WordPiece does not choose the most frequent
+progressively learns a given number of merge rules. In contrast to BPE, WordPiece does not choose the most frequent
 symbol pair, but the one that maximizes the likelihood of the training data once added to the vocabulary.
 
 So what does this mean exactly? Referring to the previous example, maximizing the likelihood of the training data is

docs/source/training.rst

@@ -14,7 +14,7 @@ Training and fine-tuning
 =======================================================================================================================
 
 Model classes in 🤗 Transformers are designed to be compatible with native PyTorch and TensorFlow 2 and can be used
-seemlessly with either. In this quickstart, we will show how to fine-tune (or train from scratch) a model using the
+seamlessly with either. In this quickstart, we will show how to fine-tune (or train from scratch) a model using the
 standard training tools available in either framework. We will also show how to use our included
 :func:`~transformers.Trainer` class which handles much of the complexity of training for you.
 

examples/README.md

@@ -16,59 +16,95 @@ limitations under the License.
 
 # Examples
 
-Version 2.9 of 🤗 Transformers introduced a new [`Trainer`](https://github.com/huggingface/transformers/blob/master/src/transformers/trainer.py) class for PyTorch, and its equivalent [`TFTrainer`](https://github.com/huggingface/transformers/blob/master/src/transformers/trainer_tf.py) for TF 2.
-Running the examples requires PyTorch 1.3.1+ or TensorFlow 2.2+.
-
-Here is the list of all our examples:
-- **grouped by task** (all official examples work for multiple models)
-- with information on whether they are **built on top of `Trainer`/`TFTrainer`** (if not, they still work, they might
-  just lack some features),
-- whether or not they leverage the [🤗 Datasets](https://github.com/huggingface/datasets) library.
-- links to **Colab notebooks** to walk through the scripts and run them easily,
-- links to **Cloud deployments** to be able to deploy large-scale trainings in the Cloud with little to no setup.
-
+This folder contains actively maintained examples of use of 🤗 Transformers organized along NLP tasks. If you are looking for an example that used to
+be in this folder, it may have moved to our [research projects](https://github.com/huggingface/transformers/tree/master/examples/research_projects) subfolder (which contains frozen snapshots of research projects).
 
 ## Important note
 
 **Important**
 
-To make sure you can successfully run the latest versions of the example scripts, you have to **install the library from source** and install some example-specific requirements.
-Execute the following steps in a new virtual environment:
-
+To make sure you can successfully run the latest versions of the example scripts, you have to **install the library from source** and install some example-specific requirements. To do this, execute the following steps in a new virtual environment:
 ```bash
 git clone https://github.com/huggingface/transformers
 cd transformers
 pip install .
-pip install -r ./examples/requirements.txt
+```
+Then cd in the example folder of your choice and run
+```bash
+pip install -r requirements.txt
 ```
 
-Alternatively, you can run the version of the examples as they were for your current version of Transformers via (for instance with v3.4.0):
+Alternatively, you can run the version of the examples as they were for your current version of Transformers via (for instance with v3.5.1):
 ```bash
-git checkout tags/v3.4.0
+git checkout tags/v3.5.1
 ```
 
 ## The Big Table of Tasks
 
+Here is the list of all our examples:
+- with information on whether they are **built on top of `Trainer`/`TFTrainer`** (if not, they still work, they might
+  just lack some features),
+- whether or not they leverage the [🤗 Datasets](https://github.com/huggingface/datasets) library.
+- links to **Colab notebooks** to walk through the scripts and run them easily,
+<!--
+Coming soon!
+- links to **Cloud deployments** to be able to deploy large-scale trainings in the Cloud with little to no setup.
+-->
+
 | Task | Example datasets | Trainer support | TFTrainer support | 🤗 Datasets | Colab
 |---|---|:---:|:---:|:---:|:---:|
 | [**`language-modeling`**](https://github.com/huggingface/transformers/tree/master/examples/language-modeling)       | Raw text        | ✅ | -  | ✅ | [![Open In Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://colab.research.google.com/github/huggingface/blog/blob/master/notebooks/01_how_to_train.ipynb)
-| [**`text-classification`**](https://github.com/huggingface/transformers/tree/master/examples/text-classification)   | GLUE, XNLI      | ✅ | ✅ | ✅ | [![Open In Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://github.com/huggingface/notebooks/blob/master/examples/text_classification.ipynb)
-| [**`token-classification`**](https://github.com/huggingface/transformers/tree/master/examples/token-classification) | CoNLL NER       | ✅ | ✅ | ✅ | -
-| [**`multiple-choice`**](https://github.com/huggingface/transformers/tree/master/examples/multiple-choice)           | SWAG, RACE, ARC | ✅ | ✅ | - | [![Open In Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://colab.research.google.com/github/ViktorAlm/notebooks/blob/master/MPC_GPU_Demo_for_TF_and_PT.ipynb)
-| [**`question-answering`**](https://github.com/huggingface/transformers/tree/master/examples/question-answering)     | SQuAD           | ✅ | ✅ | - | -
-| [**`text-generation`**](https://github.com/huggingface/transformers/tree/master/examples/text-generation)           | -               | n/a | n/a | - | [![Open In Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://colab.research.google.com/github/huggingface/blog/blob/master/notebooks/02_how_to_generate.ipynb)
-| [**`distillation`**](https://github.com/huggingface/transformers/tree/master/examples/distillation)                 | All             | - | -  | - | -
+| [**`multiple-choice`**](https://github.com/huggingface/transformers/tree/master/examples/multiple-choice)           | SWAG, RACE, ARC | ✅ | ✅ | ✅ | [![Open In Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://colab.research.google.com/github/ViktorAlm/notebooks/blob/master/MPC_GPU_Demo_for_TF_and_PT.ipynb)
+| [**`question-answering`**](https://github.com/huggingface/transformers/tree/master/examples/question-answering)     | SQuAD           | ✅ | ✅ | ✅ | [![Open In Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://github.com/huggingface/notebooks/blob/master/examples/question_answering.ipynb)
 | [**`summarization`**](https://github.com/huggingface/transformers/tree/master/examples/seq2seq)                     | CNN/Daily Mail  | ✅  | - | - | -
+| [**`text-classification`**](https://github.com/huggingface/transformers/tree/master/examples/text-classification)   | GLUE, XNLI      | ✅ | ✅ | ✅ | [![Open In Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://github.com/huggingface/notebooks/blob/master/examples/text_classification.ipynb)
+| [**`text-generation`**](https://github.com/huggingface/transformers/tree/master/examples/text-generation)           | -               | n/a | n/a | - | [![Open In Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://colab.research.google.com/github/huggingface/blog/blob/master/notebooks/02_how_to_generate.ipynb)
+| [**`token-classification`**](https://github.com/huggingface/transformers/tree/master/examples/token-classification) | CoNLL NER       | ✅ | ✅ | ✅ | [![Open In Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://github.com/huggingface/notebooks/blob/master/examples/token_classification.ipynb)
 | [**`translation`**](https://github.com/huggingface/transformers/tree/master/examples/seq2seq)                       | WMT             | ✅  | - | - | -
-| [**`bertology`**](https://github.com/huggingface/transformers/tree/master/examples/bertology)                       | -               | - | - | - | -
-| [**`adversarial`**](https://github.com/huggingface/transformers/tree/master/examples/adversarial)                   | HANS            | ✅ | - | - | -
 
 
-<br>
-
+<!--
 ## One-click Deploy to Cloud (wip)
 
 **Coming soon!**
+-->
+
+## Distributed training and mixed precision
+
+All the PyTorch scripts mentioned above work out of the box with distributed training and mixed precision, thanks to
+the [Trainer API](https://huggingface.co/transformers/main_classes/trainer.html). To launch one of them on _n_ GPUS,
+use the following command:
+
+```bash
+python -m torch.distributed.launch \
+    --nproc_per_node number_of_gpu_you_have path_to_script.py \
+	--all_arguments_of_the_script 
+```
+
+As an example, here is how you would fine-tune the BERT large model (with whole word masking) on the text
+classification MNLI task using the `run_glue` script, with 8 GPUs:
+
+```bash
+python -m torch.distributed.launch \
+    --nproc_per_node 8 text-classification/run_glue.py \
+    --model_name_or_path bert-large-uncased-whole-word-masking \
+    --task_name mnli \
+    --do_train \
+    --do_eval \
+    --max_seq_length 128 \
+    --per_device_train_batch_size 8 \
+    --learning_rate 2e-5 \
+    --num_train_epochs 3.0 \
+    --output_dir /tmp/mnli_output/
+```
+
+If you have a GPU with mixed precision capabilities (architecture Pascal or more recent), you can use mixed precision
+training with PyTorch 1.6.0 or latest, or by installing the [Apex](https://github.com/NVIDIA/apex) library for previous
+versions. Just add the flag `--fp16` to your command launching one of the scripts mentioned above!
+
+Using mixed precision training usually results in 2x-speedup for training with the same final results (as shown in
+[this table](https://github.com/huggingface/transformers/tree/master/examples/text-classification#mixed-precision-training)
+for text classification).
 
 ## Running on TPUs
 
@@ -77,27 +113,34 @@ When using Tensorflow, TPUs are supported out of the box as a `tf.distribute.Str
 When using PyTorch, we support TPUs thanks to `pytorch/xla`. For more context and information on how to setup your TPU environment refer to Google's documentation and to the
 very detailed [pytorch/xla README](https://github.com/pytorch/xla/blob/master/README.md).
 
-In this repo, we provide a very simple launcher script named [xla_spawn.py](https://github.com/huggingface/transformers/tree/master/examples/xla_spawn.py) that lets you run our example scripts on multiple TPU cores without any boilerplate.
-Just pass a `--num_cores` flag to this script, then your regular training script with its arguments (this is similar to the `torch.distributed.launch` helper for torch.distributed). 
-Note that this approach does not work for examples that use `pytorch-lightning`.
-
-For example for `run_glue`:
+In this repo, we provide a very simple launcher script named
+[xla_spawn.py](https://github.com/huggingface/transformers/tree/master/examples/xla_spawn.py) that lets you run our
+example scripts on multiple TPU cores without any boilerplate. Just pass a `--num_cores` flag to this script, then your
+regular training script with its arguments (this is similar to the `torch.distributed.launch` helper for
+`torch.distributed`):
 
 ```bash
-python examples/xla_spawn.py --num_cores 8 \
-	examples/text-classification/run_glue.py \
-	--model_name_or_path bert-base-cased \
-	--task_name mnli \
-	--data_dir ./data/glue_data/MNLI \
-	--output_dir ./models/tpu \
-	--overwrite_output_dir \
-	--do_train \
-	--do_eval \
-	--num_train_epochs 1 \
-	--save_steps 20000
+python xla_spawn.py --num_cores num_tpu_you_have \
+    path_to_script.py \
+	--all_arguments_of_the_script 
 ```
 
-Feedback and more use cases and benchmarks involving TPUs are welcome, please share with the community.
+As an example, here is how you would fine-tune the BERT large model (with whole word masking) on the text
+classification MNLI task using the `run_glue` script, with 8 TPUs:
+
+```bash
+python xla_spawn.py --num_cores 8 \
+    text-classification/run_glue.py \
+    --model_name_or_path bert-large-uncased-whole-word-masking \
+    --task_name mnli \
+    --do_train \
+    --do_eval \
+    --max_seq_length 128 \
+    --per_device_train_batch_size 8 \
+    --learning_rate 2e-5 \
+    --num_train_epochs 3.0 \
+    --output_dir /tmp/mnli_output/
+```
 
 ## Logging & Experiment tracking
 

examples/_tests_requirements.txt

@@ -0,0 +1,20 @@
+tensorboard
+scikit-learn
+seqeval
+psutil
+sacrebleu
+rouge-score
+tensorflow_datasets
+matplotlib
+git-python==1.0.3
+faiss-cpu
+streamlit
+elasticsearch
+nltk
+pandas
+datasets >= 1.1.3
+fire
+pytest
+conllu
+sentencepiece != 0.1.92
+protobuf

examples/benchmarking/README.md

@@ -1,3 +1,19 @@
+<!---
+Copyright 2020 The HuggingFace Team. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+-->
+
 # 🤗 Benchmark results
 
 Here, you can find a list of the different benchmark results created by the community.

examples/benchmarking/plot_csv_file.py

@@ -1,3 +1,17 @@
+# Copyright 2020 The HuggingFace Team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 import csv
 from collections import defaultdict
 from dataclasses import dataclass, field

examples/conftest.py

@@ -1,3 +1,17 @@
+# Copyright 2020 The HuggingFace Team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 # tests directory-specific settings - this file is run automatically
 # by pytest before any tests are run
 

examples/contrib/README.md

@@ -1,5 +0,0 @@
-# Community contributed examples
-
-This folder contains examples which are not actively maintained (mostly contributed by the community).
-
-Using these examples together with a recent version of the library usually requires to make small (sometimes big) adaptations to get the scripts working.

examples/language-modeling/README.md

@@ -1,3 +1,19 @@
+<!---
+Copyright 2020 The HuggingFace Team. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+-->
+
 ## Language model training
 
 Fine-tuning (or training from scratch) the library models for language modeling on a text dataset for GPT, GPT-2,
@@ -9,12 +25,20 @@ objectives in our [model summary](https://huggingface.co/transformers/model_summ
 These scripts leverage the 🤗 Datasets library and the Trainer API. You can easily customize them to your needs if you
 need extra processing on your datasets.
 
-**Note:** The old script `run_language_modeling.py` is still available
-[here](https://github.com/huggingface/transformers/blob/master/examples/contrib/legacy/run_language_modeling.py).
+**Note:** The old script `run_language_modeling.py` is still available [here](https://github.com/huggingface/transformers/blob/master/examples/legacy/run_language_modeling.py).
 
 The following examples, will run on a datasets hosted on our [hub](https://huggingface.co/datasets) or with your own
 text files for training and validation. We give examples of both below.
 
+### Datasets
+
+The main dataset used in the examples below is:
+
+```bash
+wget https://s3.amazonaws.com/research.metamind.io/wikitext/wikitext-2-raw-v1.zip
+unzip wikitext-2-raw-v1.zip
+```
+
 ### GPT-2/GPT and causal language modeling
 
 The following example fine-tunes GPT-2 on WikiText-2. We're using the raw WikiText-2 (no tokens were replaced before

examples/language-modeling/requirements.txt

@@ -0,0 +1,3 @@
+datasets >= 1.1.3
+sentencepiece != 0.1.92
+protobuf

examples/language-modeling/run_clm.py

@@ -113,6 +113,12 @@ class DataTrainingArguments:
     overwrite_cache: bool = field(
         default=False, metadata={"help": "Overwrite the cached training and evaluation sets"}
     )
+    validation_split_percentage: Optional[int] = field(
+        default=5,
+        metadata={
+            "help": "The percentage of the train set used as validation set in case there's no validation split"
+        },
+    )
     preprocessing_num_workers: Optional[int] = field(
         default=None,
         metadata={"help": "The number of processes to use for the preprocessing."},
@@ -188,6 +194,17 @@ def main():
     if data_args.dataset_name is not None:
         # Downloading and loading a dataset from the hub.
         datasets = load_dataset(data_args.dataset_name, data_args.dataset_config_name)
+        if "validation" not in datasets.keys():
+            datasets["validation"] = load_dataset(
+                data_args.dataset_name,
+                data_args.dataset_config_name,
+                split=f"train[:{data_args.validation_split_percentage}%]",
+            )
+            datasets["train"] = load_dataset(
+                data_args.dataset_name,
+                data_args.dataset_config_name,
+                split=f"train[{data_args.validation_split_percentage}%:]",
+            )
     else:
         data_files = {}
         if data_args.train_file is not None:
@@ -324,9 +341,20 @@ def main():
             if (model_args.model_name_or_path is not None and os.path.isdir(model_args.model_name_or_path))
             else None
         )
-        trainer.train(model_path=model_path)
+        train_result = trainer.train(model_path=model_path)
         trainer.save_model()  # Saves the tokenizer too for easy upload
 
+        output_train_file = os.path.join(training_args.output_dir, "train_results.txt")
+        if trainer.is_world_process_zero():
+            with open(output_train_file, "w") as writer:
+                logger.info("***** Train results *****")
+                for key, value in sorted(train_result.metrics.items()):
+                    logger.info(f"  {key} = {value}")
+                    writer.write(f"{key} = {value}\n")
+
+            # Need to save the state, since Trainer.save_model saves only the tokenizer with the model
+            trainer.state.save_to_json(os.path.join(training_args.output_dir, "trainer_state.json"))
+
     # Evaluation
     results = {}
     if training_args.do_eval:
@@ -341,7 +369,7 @@ def main():
         if trainer.is_world_process_zero():
             with open(output_eval_file, "w") as writer:
                 logger.info("***** Eval results *****")
-                for key, value in results.items():
+                for key, value in sorted(results.items()):
                     logger.info(f"  {key} = {value}")
                     writer.write(f"{key} = {value}\n")
 

examples/language-modeling/run_mlm.py

@@ -103,6 +103,12 @@ class DataTrainingArguments:
     overwrite_cache: bool = field(
         default=False, metadata={"help": "Overwrite the cached training and evaluation sets"}
     )
+    validation_split_percentage: Optional[int] = field(
+        default=5,
+        metadata={
+            "help": "The percentage of the train set used as validation set in case there's no validation split"
+        },
+    )
     max_seq_length: Optional[int] = field(
         default=None,
         metadata={
@@ -199,6 +205,17 @@ def main():
     if data_args.dataset_name is not None:
         # Downloading and loading a dataset from the hub.
         datasets = load_dataset(data_args.dataset_name, data_args.dataset_config_name)
+        if "validation" not in datasets.keys():
+            datasets["validation"] = load_dataset(
+                data_args.dataset_name,
+                data_args.dataset_config_name,
+                split=f"train[:{data_args.validation_split_percentage}%]",
+            )
+            datasets["train"] = load_dataset(
+                data_args.dataset_name,
+                data_args.dataset_config_name,
+                split=f"train[{data_args.validation_split_percentage}%:]",
+            )
     else:
         data_files = {}
         if data_args.train_file is not None:
@@ -359,9 +376,20 @@ def main():
             if (model_args.model_name_or_path is not None and os.path.isdir(model_args.model_name_or_path))
             else None
         )
-        trainer.train(model_path=model_path)
+        train_result = trainer.train(model_path=model_path)
         trainer.save_model()  # Saves the tokenizer too for easy upload
 
+        output_train_file = os.path.join(training_args.output_dir, "train_results.txt")
+        if trainer.is_world_process_zero():
+            with open(output_train_file, "w") as writer:
+                logger.info("***** Train results *****")
+                for key, value in sorted(train_result.metrics.items()):
+                    logger.info(f"  {key} = {value}")
+                    writer.write(f"{key} = {value}\n")
+
+            # Need to save the state, since Trainer.save_model saves only the tokenizer with the model
+            trainer.state.save_to_json(os.path.join(training_args.output_dir, "trainer_state.json"))
+
     # Evaluation
     results = {}
     if training_args.do_eval:
@@ -376,7 +404,7 @@ def main():
         if trainer.is_world_process_zero():
             with open(output_eval_file, "w") as writer:
                 logger.info("***** Eval results *****")
-                for key, value in results.items():
+                for key, value in sorted(results.items()):
                     logger.info(f"  {key} = {value}")
                     writer.write(f"{key} = {value}\n")
 

examples/language-modeling/run_mlm_flax.py

@@ -0,0 +1,660 @@
+# coding=utf-8
+# Copyright 2020 The HuggingFace Team All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""
+Fine-tuning the library models for masked language modeling (BERT, ALBERT, RoBERTa...) with whole word masking on a
+text file or a dataset.
+
+Here is the full list of checkpoints on the hub that can be fine-tuned by this script:
+https://huggingface.co/models?filter=masked-lm
+"""
+import logging
+import os
+import sys
+from dataclasses import dataclass, field
+
+# You can also adapt this script on your own masked language modeling task. Pointers for this are left as comments.
+from pathlib import Path
+from typing import Dict, List, Optional, Tuple
+
+import numpy as np
+from datasets import load_dataset
+from tqdm import tqdm
+
+import jax
+import jax.numpy as jnp
+from flax import jax_utils
+from flax.optim import Adam
+from flax.training import common_utils
+from flax.training.common_utils import get_metrics
+from jax.nn import log_softmax
+from transformers import (
+    CONFIG_MAPPING,
+    MODEL_FOR_MASKED_LM_MAPPING,
+    AutoConfig,
+    AutoTokenizer,
+    FlaxBertForMaskedLM,
+    HfArgumentParser,
+    PreTrainedTokenizerBase,
+    TensorType,
+    TrainingArguments,
+    is_tensorboard_available,
+    set_seed,
+)
+
+
+# Cache the result
+has_tensorboard = is_tensorboard_available()
+if has_tensorboard:
+    try:
+        from flax.metrics.tensorboard import SummaryWriter
+    except ImportError as ie:
+        has_tensorboard = False
+        print(f"Unable to display metrics through TensorBoard because some package are not installed: {ie}")
+
+else:
+    print(
+        "Unable to display metrics through TensorBoard because the package is not installed: "
+        "Please run pip install tensorboard to enable."
+    )
+
+
+MODEL_CONFIG_CLASSES = list(MODEL_FOR_MASKED_LM_MAPPING.keys())
+MODEL_TYPES = tuple(conf.model_type for conf in MODEL_CONFIG_CLASSES)
+
+
+@dataclass
+class ModelArguments:
+    """
+    Arguments pertaining to which model/config/tokenizer we are going to fine-tune, or train from scratch.
+    """
+
+    model_name_or_path: Optional[str] = field(
+        default=None,
+        metadata={
+            "help": "The model checkpoint for weights initialization."
+            "Don't set if you want to train a model from scratch."
+        },
+    )
+    model_type: Optional[str] = field(
+        default=None,
+        metadata={"help": "If training from scratch, pass a model type from the list: " + ", ".join(MODEL_TYPES)},
+    )
+    config_name: Optional[str] = field(
+        default=None, metadata={"help": "Pretrained config name or path if not the same as model_name"}
+    )
+    tokenizer_name: Optional[str] = field(
+        default=None, metadata={"help": "Pretrained tokenizer name or path if not the same as model_name"}
+    )
+    cache_dir: Optional[str] = field(
+        default=None, metadata={"help": "Where do you want to store the pretrained models downloaded from s3"}
+    )
+    use_fast_tokenizer: bool = field(
+        default=True,
+        metadata={"help": "Whether to use one of the fast tokenizer (backed by the tokenizers library) or not."},
+    )
+
+
+@dataclass
+class DataTrainingArguments:
+    """
+    Arguments pertaining to what data we are going to input our model for training and eval.
+    """
+
+    dataset_name: Optional[str] = field(
+        default=None, metadata={"help": "The name of the dataset to use (via the datasets library)."}
+    )
+    dataset_config_name: Optional[str] = field(
+        default=None, metadata={"help": "The configuration name of the dataset to use (via the datasets library)."}
+    )
+    train_file: Optional[str] = field(default=None, metadata={"help": "The input training data file (a text file)."})
+    validation_file: Optional[str] = field(
+        default=None,
+        metadata={"help": "An optional input evaluation data file to evaluate the perplexity on (a text file)."},
+    )
+    train_ref_file: Optional[str] = field(
+        default=None,
+        metadata={"help": "An optional input train ref data file for whole word masking in Chinese."},
+    )
+    validation_ref_file: Optional[str] = field(
+        default=None,
+        metadata={"help": "An optional input validation ref data file for whole word masking in Chinese."},
+    )
+    overwrite_cache: bool = field(
+        default=False, metadata={"help": "Overwrite the cached training and evaluation sets"}
+    )
+    validation_split_percentage: Optional[int] = field(
+        default=5,
+        metadata={
+            "help": "The percentage of the train set used as validation set in case there's no validation split"
+        },
+    )
+    max_seq_length: Optional[int] = field(
+        default=None,
+        metadata={
+            "help": "The maximum total input sequence length after tokenization. Sequences longer "
+            "than this will be truncated. Default to the max input length of the model."
+        },
+    )
+    preprocessing_num_workers: Optional[int] = field(
+        default=None,
+        metadata={"help": "The number of processes to use for the preprocessing."},
+    )
+    mlm_probability: float = field(
+        default=0.15, metadata={"help": "Ratio of tokens to mask for masked language modeling loss"}
+    )
+    pad_to_max_length: bool = field(
+        default=False,
+        metadata={
+            "help": "Whether to pad all samples to `max_seq_length`. "
+            "If False, will pad the samples dynamically when batching to the maximum length in the batch."
+        },
+    )
+
+    def __post_init__(self):
+        if self.dataset_name is None and self.train_file is None and self.validation_file is None:
+            raise ValueError("Need either a dataset name or a training/validation file.")
+        else:
+            if self.train_file is not None:
+                extension = self.train_file.split(".")[-1]
+                assert extension in ["csv", "json", "txt"], "`train_file` should be a csv, a json or a txt file."
+            if self.validation_file is not None:
+                extension = self.validation_file.split(".")[-1]
+                assert extension in ["csv", "json", "txt"], "`validation_file` should be a csv, a json or a txt file."
+
+
+# Adapted from transformers/data/data_collator.py
+# Letting here for now, let's discuss where it should live
+@dataclass
+class FlaxDataCollatorForLanguageModeling:
+    """
+    Data collator used for language modeling. Inputs are dynamically padded to the maximum length of a batch if they
+    are not all of the same length.
+
+    Args:
+        tokenizer (:class:`~transformers.PreTrainedTokenizer` or :class:`~transformers.PreTrainedTokenizerFast`):
+            The tokenizer used for encoding the data.
+        mlm (:obj:`bool`, `optional`, defaults to :obj:`True`):
+            Whether or not to use masked language modeling. If set to :obj:`False`, the labels are the same as the
+            inputs with the padding tokens ignored (by setting them to -100). Otherwise, the labels are -100 for
+            non-masked tokens and the value to predict for the masked token.
+        mlm_probability (:obj:`float`, `optional`, defaults to 0.15):
+            The probability with which to (randomly) mask tokens in the input, when :obj:`mlm` is set to :obj:`True`.
+
+    .. note::
+
+        For best performance, this data collator should be used with a dataset having items that are dictionaries or
+        BatchEncoding, with the :obj:`"special_tokens_mask"` key, as returned by a
+        :class:`~transformers.PreTrainedTokenizer` or a :class:`~transformers.PreTrainedTokenizerFast` with the
+        argument :obj:`return_special_tokens_mask=True`.
+    """
+
+    tokenizer: PreTrainedTokenizerBase
+    mlm: bool = True
+    mlm_probability: float = 0.15
+
+    def __post_init__(self):
+        if self.mlm and self.tokenizer.mask_token is None:
+            raise ValueError(
+                "This tokenizer does not have a mask token which is necessary for masked language modeling. "
+                "You should pass `mlm=False` to train on causal language modeling instead."
+            )
+
+    def __call__(self, examples: List[Dict[str, np.ndarray]], pad_to_multiple_of: int) -> Dict[str, np.ndarray]:
+        # Handle dict or lists with proper padding and conversion to tensor.
+        batch = self.tokenizer.pad(examples, pad_to_multiple_of=pad_to_multiple_of, return_tensors=TensorType.NUMPY)
+
+        # If special token mask has been preprocessed, pop it from the dict.
+        special_tokens_mask = batch.pop("special_tokens_mask", None)
+        if self.mlm:
+            batch["input_ids"], batch["labels"] = self.mask_tokens(
+                batch["input_ids"], special_tokens_mask=special_tokens_mask
+            )
+        else:
+            labels = batch["input_ids"].copy()
+            if self.tokenizer.pad_token_id is not None:
+                labels[labels == self.tokenizer.pad_token_id] = -100
+            batch["labels"] = labels
+        return batch
+
+    def mask_tokens(
+        self, inputs: np.ndarray, special_tokens_mask: Optional[np.ndarray]
+    ) -> Tuple[jnp.ndarray, jnp.ndarray]:
+        """
+        Prepare masked tokens inputs/labels for masked language modeling: 80% MASK, 10% random, 10% original.
+        """
+        labels = inputs.copy()
+        # We sample a few tokens in each sequence for MLM training (with probability `self.mlm_probability`)
+        probability_matrix = np.full(labels.shape, self.mlm_probability)
+        special_tokens_mask = special_tokens_mask.astype("bool")
+
+        probability_matrix[special_tokens_mask] = 0.0
+        masked_indices = np.random.binomial(1, probability_matrix).astype("bool")
+        labels[~masked_indices] = -100  # We only compute loss on masked tokens
+
+        # 80% of the time, we replace masked input tokens with tokenizer.mask_token ([MASK])
+        indices_replaced = np.random.binomial(1, np.full(labels.shape, 0.8)).astype("bool") & masked_indices
+        inputs[indices_replaced] = self.tokenizer.convert_tokens_to_ids(self.tokenizer.mask_token)
+
+        # 10% of the time, we replace masked input tokens with random word
+        indices_random = np.random.binomial(1, np.full(labels.shape, 0.5)).astype("bool")
+        indices_random &= masked_indices & ~indices_replaced
+
+        random_words = np.random.randint(self.tokenizer.vocab_size, size=labels.shape, dtype="i4")
+        inputs[indices_random] = random_words[indices_random]
+
+        # The rest of the time (10% of the time) we keep the masked input tokens unchanged
+        return inputs, labels
+
+
+def create_learning_rate_scheduler(
+    factors="constant * linear_warmup * rsqrt_decay",
+    base_learning_rate=0.5,
+    warmup_steps=1000,
+    decay_factor=0.5,
+    steps_per_decay=20000,
+    steps_per_cycle=100000,
+):
+    """Creates learning rate schedule.
+    Interprets factors in the factors string which can consist of:
+    * constant: interpreted as the constant value,
+    * linear_warmup: interpreted as linear warmup until warmup_steps,
+    * rsqrt_decay: divide by square root of max(step, warmup_steps)
+    * rsqrt_normalized_decay: divide by square root of max(step/warmup_steps, 1)
+    * decay_every: Every k steps decay the learning rate by decay_factor.
+    * cosine_decay: Cyclic cosine decay, uses steps_per_cycle parameter.
+    Args:
+      factors: string, factors separated by "*" that defines the schedule.
+      base_learning_rate: float, the starting constant for the lr schedule.
+      warmup_steps: int, how many steps to warm up for in the warmup schedule.
+      decay_factor: float, the amount to decay the learning rate by.
+      steps_per_decay: int, how often to decay the learning rate.
+      steps_per_cycle: int, steps per cycle when using cosine decay.
+    Returns:
+      a function learning_rate(step): float -> {"learning_rate": float}, the
+      step-dependent lr.
+    """
+    factors = [n.strip() for n in factors.split("*")]
+
+    def step_fn(step):
+        """Step to learning rate function."""
+        ret = 1.0
+        for name in factors:
+            if name == "constant":
+                ret *= base_learning_rate
+            elif name == "linear_warmup":
+                ret *= jnp.minimum(1.0, step / warmup_steps)
+            elif name == "rsqrt_decay":
+                ret /= jnp.sqrt(jnp.maximum(step, warmup_steps))
+            elif name == "rsqrt_normalized_decay":
+                ret *= jnp.sqrt(warmup_steps)
+                ret /= jnp.sqrt(jnp.maximum(step, warmup_steps))
+            elif name == "decay_every":
+                ret *= decay_factor ** (step // steps_per_decay)
+            elif name == "cosine_decay":
+                progress = jnp.maximum(0.0, (step - warmup_steps) / float(steps_per_cycle))
+                ret *= jnp.maximum(0.0, 0.5 * (1.0 + jnp.cos(jnp.pi * (progress % 1.0))))
+            else:
+                raise ValueError("Unknown factor %s." % name)
+        return jnp.asarray(ret, dtype=jnp.float32)
+
+    return step_fn
+
+
+def compute_metrics(logits, labels, weights, label_smoothing=0.0):
+    """Compute summary metrics."""
+    loss, normalizer = cross_entropy(logits, labels, weights, label_smoothing)
+    acc, _ = accuracy(logits, labels, weights)
+    metrics = {"loss": loss, "accuracy": acc, "normalizer": normalizer}
+    metrics = jax.lax.psum(metrics, axis_name="batch")
+    return metrics
+
+
+def accuracy(logits, targets, weights=None):
+    """Compute weighted accuracy for log probs and targets.
+    Args:
+     logits: [batch, length, num_classes] float array.
+     targets: categorical targets [batch, length] int array.
+     weights: None or array of shape [batch, length]
+    Returns:
+      Tuple of scalar loss and batch normalizing factor.
+    """
+    if logits.ndim != targets.ndim + 1:
+        raise ValueError(
+            "Incorrect shapes. Got shape %s logits and %s targets" % (str(logits.shape), str(targets.shape))
+        )
+
+    loss = jnp.equal(jnp.argmax(logits, axis=-1), targets)
+    loss *= weights
+
+    return loss.sum(), weights.sum()
+
+
+def cross_entropy(logits, targets, weights=None, label_smoothing=0.0):
+    """Compute cross entropy and entropy for log probs and targets.
+    Args:
+     logits: [batch, length, num_classes] float array.
+     targets: categorical targets [batch, length] int array.
+     weights: None or array of shape [batch, length]
+     label_smoothing: label smoothing constant, used to determine the on and off values.
+    Returns:
+      Tuple of scalar loss and batch normalizing factor.
+    """
+    if logits.ndim != targets.ndim + 1:
+        raise ValueError(
+            "Incorrect shapes. Got shape %s logits and %s targets" % (str(logits.shape), str(targets.shape))
+        )
+
+    vocab_size = logits.shape[-1]
+    confidence = 1.0 - label_smoothing
+    low_confidence = (1.0 - confidence) / (vocab_size - 1)
+    normalizing_constant = -(
+        confidence * jnp.log(confidence) + (vocab_size - 1) * low_confidence * jnp.log(low_confidence + 1e-20)
+    )
+    soft_targets = common_utils.onehot(targets, vocab_size, on_value=confidence, off_value=low_confidence)
+
+    loss = -jnp.sum(soft_targets * log_softmax(logits), axis=-1)
+    loss = loss - normalizing_constant
+
+    if weights is not None:
+        loss = loss * weights
+        normalizing_factor = weights.sum()
+    else:
+        normalizing_factor = np.prod(targets.shape)
+
+    return loss.sum(), normalizing_factor
+
+
+def training_step(optimizer, batch, dropout_rng):
+    dropout_rng, new_dropout_rng = jax.random.split(dropout_rng)
+
+    def loss_fn(params):
+        targets = batch.pop("labels")
+
+        # Hide away tokens which doesn't participate in the optimization
+        token_mask = jnp.where(targets > 0, 1.0, 0.0)
+
+        logits = model(**batch, params=params, dropout_rng=dropout_rng, train=True)[0]
+        loss, weight_sum = cross_entropy(logits, targets, token_mask)
+        return loss / weight_sum
+
+    step = optimizer.state.step
+    lr = lr_scheduler_fn(step)
+    grad_fn = jax.value_and_grad(loss_fn)
+    loss, grad = grad_fn(optimizer.target)
+    grad = jax.lax.pmean(grad, "batch")
+    optimizer = optimizer.apply_gradient(grad, learning_rate=lr)
+
+    return loss, optimizer, new_dropout_rng
+
+
+def eval_step(params, batch):
+    """
+    Calculate evaluation metrics on a batch.
+    """
+    targets = batch.pop("labels")
+
+    # Hide away tokens which doesn't participate in the optimization
+    token_mask = jnp.where(targets > 0, 1.0, 0.0)
+    logits = model(**batch, params=params, train=False)[0]
+
+    return compute_metrics(logits, targets, token_mask)
+
+
+def generate_batch_splits(samples_idx: jnp.ndarray, batch_size: int) -> jnp.ndarray:
+    nb_samples = len(samples_idx)
+    samples_to_remove = nb_samples % batch_size
+
+    if samples_to_remove != 0:
+        samples_idx = samples_idx[:-samples_to_remove]
+    sections_split = nb_samples // batch_size
+    batch_idx = np.split(samples_idx, sections_split)
+    return batch_idx
+
+
+if __name__ == "__main__":
+    # See all possible arguments in src/transformers/training_args.py
+    # or by passing the --help flag to this script.
+    # We now keep distinct sets of args, for a cleaner separation of concerns.
+
+    parser = HfArgumentParser((ModelArguments, DataTrainingArguments, TrainingArguments))
+    if len(sys.argv) == 2 and sys.argv[1].endswith(".json"):
+        # If we pass only one argument to the script and it's the path to a json file,
+        # let's parse it to get our arguments.
+        model_args, data_args, training_args = parser.parse_json_file(json_file=os.path.abspath(sys.argv[1]))
+    else:
+        model_args, data_args, training_args = parser.parse_args_into_dataclasses()
+
+    if (
+        os.path.exists(training_args.output_dir)
+        and os.listdir(training_args.output_dir)
+        and training_args.do_train
+        and not training_args.overwrite_output_dir
+    ):
+        raise ValueError(
+            f"Output directory ({training_args.output_dir}) already exists and is not empty."
+            "Use --overwrite_output_dir to overcome."
+        )
+
+    # Setup logging
+    logging.basicConfig(
+        format="%(asctime)s - %(levelname)s - %(name)s -   %(message)s",
+        level="NOTSET",
+        datefmt="[%X]",
+    )
+
+    # Log on each process the small summary:
+    logger = logging.getLogger(__name__)
+    logger.warning(
+        f"Process rank: {training_args.local_rank}, device: {training_args.device}, n_gpu: {training_args.n_gpu}"
+        + f"distributed training: {bool(training_args.local_rank != -1)}, 16-bits training: {training_args.fp16}"
+    )
+
+    # Set the verbosity to info of the Transformers logger (on main process only):
+    logger.info("Training/evaluation parameters %s", training_args)
+
+    # Set seed before initializing model.
+    set_seed(training_args.seed)
+
+    # Get the datasets: you can either provide your own CSV/JSON/TXT training and evaluation files (see below)
+    # or just provide the name of one of the public datasets available on the hub at https://huggingface.co/datasets/
+    # (the dataset will be downloaded automatically from the datasets Hub).
+    #
+    # For CSV/JSON files, this script will use the column called 'text' or the first column if no column called
+    # 'text' is found. You can easily tweak this behavior (see below).
+    #
+    # In distributed training, the load_dataset function guarantees that only one local process can concurrently
+    # download the dataset.
+    if data_args.dataset_name is not None:
+        # Downloading and loading a dataset from the hub.
+        datasets = load_dataset(data_args.dataset_name, data_args.dataset_config_name)
+        if "validation" not in datasets.keys():
+            datasets["validation"] = load_dataset(
+                data_args.dataset_name,
+                data_args.dataset_config_name,
+                split=f"train[:{data_args.validation_split_percentage}%]",
+            )
+            datasets["train"] = load_dataset(
+                data_args.dataset_name,
+                data_args.dataset_config_name,
+                split=f"train[{data_args.validation_split_percentage}%:]",
+            )
+    else:
+        data_files = {}
+        if data_args.train_file is not None:
+            data_files["train"] = data_args.train_file
+        if data_args.validation_file is not None:
+            data_files["validation"] = data_args.validation_file
+        extension = data_args.train_file.split(".")[-1]
+        if extension == "txt":
+            extension = "text"
+        datasets = load_dataset(extension, data_files=data_files)
+    # See more about loading any type of standard or custom dataset (from files, python dict, pandas DataFrame, etc) at
+    # https://huggingface.co/docs/datasets/loading_datasets.html.
+
+    # Load pretrained model and tokenizer
+
+    # Distributed training:
+    # The .from_pretrained methods guarantee that only one local process can concurrently
+    # download model & vocab.
+    if model_args.config_name:
+        config = AutoConfig.from_pretrained(model_args.config_name, cache_dir=model_args.cache_dir)
+    elif model_args.model_name_or_path:
+        config = AutoConfig.from_pretrained(model_args.model_name_or_path, cache_dir=model_args.cache_dir)
+    else:
+        config = CONFIG_MAPPING[model_args.model_type]()
+        logger.warning("You are instantiating a new config instance from scratch.")
+
+    if model_args.tokenizer_name:
+        tokenizer = AutoTokenizer.from_pretrained(
+            model_args.tokenizer_name, cache_dir=model_args.cache_dir, use_fast=model_args.use_fast_tokenizer
+        )
+    elif model_args.model_name_or_path:
+        tokenizer = AutoTokenizer.from_pretrained(
+            model_args.model_name_or_path, cache_dir=model_args.cache_dir, use_fast=model_args.use_fast_tokenizer
+        )
+    else:
+        raise ValueError(
+            "You are instantiating a new tokenizer from scratch. This is not supported by this script."
+            "You can do it from another script, save it, and load it from here, using --tokenizer_name."
+        )
+
+    # Preprocessing the datasets.
+    # First we tokenize all the texts.
+    if training_args.do_train:
+        column_names = datasets["train"].column_names
+    else:
+        column_names = datasets["validation"].column_names
+    text_column_name = "text" if "text" in column_names else column_names[0]
+
+    padding = "max_length" if data_args.pad_to_max_length else False
+
+    def tokenize_function(examples):
+        # Remove empty lines
+        examples = [line for line in examples if len(line) > 0 and not line.isspace()]
+        return tokenizer(
+            examples,
+            return_special_tokens_mask=True,
+            padding=padding,
+            truncation=True,
+            max_length=data_args.max_seq_length,
+        )
+
+    tokenized_datasets = datasets.map(
+        tokenize_function,
+        input_columns=[text_column_name],
+        batched=True,
+        num_proc=data_args.preprocessing_num_workers,
+        remove_columns=column_names,
+        load_from_cache_file=not data_args.overwrite_cache,
+    )
+
+    # Enable tensorboard only on the master node
+    if has_tensorboard and jax.host_id() == 0:
+        summary_writer = SummaryWriter(log_dir=Path(training_args.output_dir).joinpath("logs").as_posix())
+
+    # Data collator
+    # This one will take care of randomly masking the tokens.
+    data_collator = FlaxDataCollatorForLanguageModeling(tokenizer=tokenizer, mlm_probability=data_args.mlm_probability)
+
+    # Initialize our training
+    rng = jax.random.PRNGKey(training_args.seed)
+    dropout_rngs = jax.random.split(rng, jax.local_device_count())
+
+    model = FlaxBertForMaskedLM.from_pretrained(
+        "bert-base-cased",
+        dtype=jnp.float32,
+        input_shape=(training_args.train_batch_size, config.max_position_embeddings),
+        seed=training_args.seed,
+        dropout_rate=0.1,
+    )
+
+    # Setup optimizer
+    optimizer = Adam(
+        learning_rate=training_args.learning_rate,
+        weight_decay=training_args.weight_decay,
+        beta1=training_args.adam_beta1,
+        beta2=training_args.adam_beta2,
+    ).create(model.params)
+
+    # Create learning rate scheduler
+    # warmup_steps = 0 causes the Flax optimizer to return NaNs; warmup_steps = 1 is functionally equivalent.
+    lr_scheduler_fn = create_learning_rate_scheduler(
+        base_learning_rate=training_args.learning_rate, warmup_steps=min(training_args.warmup_steps, 1)
+    )
+
+    # Create parallel version of the training and evaluation steps
+    p_training_step = jax.pmap(training_step, "batch", donate_argnums=(0,))
+    p_eval_step = jax.pmap(eval_step, "batch", donate_argnums=(0,))
+
+    # Replicate the optimizer on each device
+    optimizer = jax_utils.replicate(optimizer)
+
+    # Store some constant
+    nb_epochs = int(training_args.num_train_epochs)
+    batch_size = int(training_args.train_batch_size)
+    eval_batch_size = int(training_args.eval_batch_size)
+
+    epochs = tqdm(range(nb_epochs), desc=f"Epoch ... (1/{nb_epochs})", position=0)
+    for epoch in epochs:
+
+        # ======================== Training ================================
+        # Create sampling rng
+        rng, training_rng, eval_rng = jax.random.split(rng, 3)
+
+        # Generate an epoch by shuffling sampling indices from the train dataset
+        nb_training_samples = len(tokenized_datasets["train"])
+        training_samples_idx = jax.random.permutation(training_rng, jnp.arange(nb_training_samples))
+        training_batch_idx = generate_batch_splits(training_samples_idx, batch_size)
+
+        # Gather the indexes for creating the batch and do a training step
+        for batch_idx in tqdm(training_batch_idx, desc="Training...", position=1):
+            samples = [tokenized_datasets["train"][int(idx)] for idx in batch_idx]
+            model_inputs = data_collator(samples, pad_to_multiple_of=16)
+
+            # Model forward
+            model_inputs = common_utils.shard(model_inputs.data)
+            loss, optimizer, dropout_rngs = p_training_step(optimizer, model_inputs, dropout_rngs)
+
+        epochs.write(f"Loss: {loss}")
+
+        # ======================== Evaluating ==============================
+        nb_eval_samples = len(tokenized_datasets["validation"])
+        eval_samples_idx = jnp.arange(nb_eval_samples)
+        eval_batch_idx = generate_batch_splits(eval_samples_idx, eval_batch_size)
+
+        eval_metrics = []
+        for i, batch_idx in enumerate(tqdm(eval_batch_idx, desc="Evaluating ...", position=2)):
+            samples = [tokenized_datasets["validation"][int(idx)] for idx in batch_idx]
+            model_inputs = data_collator(samples, pad_to_multiple_of=16)
+
+            # Model forward
+            model_inputs = common_utils.shard(model_inputs.data)
+            metrics = p_eval_step(optimizer.target, model_inputs)
+            eval_metrics.append(metrics)
+
+        eval_metrics_np = get_metrics(eval_metrics)
+        eval_metrics_np = jax.tree_map(jnp.sum, eval_metrics_np)
+        eval_normalizer = eval_metrics_np.pop("normalizer")
+        eval_summary = jax.tree_map(lambda x: x / eval_normalizer, eval_metrics_np)
+
+        # Update progress bar
+        epochs.desc = (
+            f"Epoch... ({epoch + 1}/{nb_epochs} | Loss: {eval_summary['loss']}, Acc: {eval_summary['accuracy']})"
+        )
+
+        # Save metrics
+        if has_tensorboard and jax.host_id() == 0:
+            for name, value in eval_summary.items():
+                summary_writer.scalar(name, value, epoch)

examples/language-modeling/run_mlm_wwm.py

@@ -91,6 +91,12 @@ class DataTrainingArguments:
     Arguments pertaining to what data we are going to input our model for training and eval.
     """
 
+    dataset_name: Optional[str] = field(
+        default=None, metadata={"help": "The name of the dataset to use (via the datasets library)."}
+    )
+    dataset_config_name: Optional[str] = field(
+        default=None, metadata={"help": "The configuration name of the dataset to use (via the datasets library)."}
+    )
     train_file: Optional[str] = field(default=None, metadata={"help": "The input training data file (a text file)."})
     validation_file: Optional[str] = field(
         default=None,
@@ -107,6 +113,12 @@ class DataTrainingArguments:
     overwrite_cache: bool = field(
         default=False, metadata={"help": "Overwrite the cached training and evaluation sets"}
     )
+    validation_split_percentage: Optional[int] = field(
+        default=5,
+        metadata={
+            "help": "The percentage of the train set used as validation set in case there's no validation split"
+        },
+    )
     max_seq_length: Optional[int] = field(
         default=None,
         metadata={
@@ -203,15 +215,30 @@ def main():
     #
     # In distributed training, the load_dataset function guarantee that only one local process can concurrently
     # download the dataset.
-    data_files = {}
-    if data_args.train_file is not None:
-        data_files["train"] = data_args.train_file
-    if data_args.validation_file is not None:
-        data_files["validation"] = data_args.validation_file
-    extension = data_args.train_file.split(".")[-1]
-    if extension == "txt":
-        extension = "text"
-    datasets = load_dataset(extension, data_files=data_files)
+    if data_args.dataset_name is not None:
+        # Downloading and loading a dataset from the hub.
+        datasets = load_dataset(data_args.dataset_name, data_args.dataset_config_name)
+        if "validation" not in datasets.keys():
+            datasets["validation"] = load_dataset(
+                data_args.dataset_name,
+                data_args.dataset_config_name,
+                split=f"train[:{data_args.validation_split_percentage}%]",
+            )
+            datasets["train"] = load_dataset(
+                data_args.dataset_name,
+                data_args.dataset_config_name,
+                split=f"train[{data_args.validation_split_percentage}%:]",
+            )
+    else:
+        data_files = {}
+        if data_args.train_file is not None:
+            data_files["train"] = data_args.train_file
+        if data_args.validation_file is not None:
+            data_files["validation"] = data_args.validation_file
+        extension = data_args.train_file.split(".")[-1]
+        if extension == "txt":
+            extension = "text"
+        datasets = load_dataset(extension, data_files=data_files)
     # See more about loading any type of standard or custom dataset (from files, python dict, pandas DataFrame, etc) at
     # https://huggingface.co/docs/datasets/loading_datasets.html.
 
@@ -281,7 +308,7 @@ def main():
     # Add the chinese references if provided
     if data_args.train_ref_file is not None:
         tokenized_datasets["train"] = add_chinese_references(tokenized_datasets["train"], data_args.train_ref_file)
-    if data_args.valid_ref_file is not None:
+    if data_args.validation_ref_file is not None:
         tokenized_datasets["validation"] = add_chinese_references(
             tokenized_datasets["validation"], data_args.validation_ref_file
         )
@@ -307,9 +334,20 @@ def main():
             if (model_args.model_name_or_path is not None and os.path.isdir(model_args.model_name_or_path))
             else None
         )
-        trainer.train(model_path=model_path)
+        train_result = trainer.train(model_path=model_path)
         trainer.save_model()  # Saves the tokenizer too for easy upload
 
+        output_train_file = os.path.join(training_args.output_dir, "train_results.txt")
+        if trainer.is_world_process_zero():
+            with open(output_train_file, "w") as writer:
+                logger.info("***** Train results *****")
+                for key, value in sorted(train_result.metrics.items()):
+                    logger.info(f"  {key} = {value}")
+                    writer.write(f"{key} = {value}\n")
+
+            # Need to save the state, since Trainer.save_model saves only the tokenizer with the model
+            trainer.state.save_to_json(os.path.join(training_args.output_dir, "trainer_state.json"))
+
     # Evaluation
     results = {}
     if training_args.do_eval:
@@ -324,7 +362,7 @@ def main():
         if trainer.is_world_process_zero():
             with open(output_eval_file, "w") as writer:
                 logger.info("***** Eval results *****")
-                for key, value in results.items():
+                for key, value in sorted(results.items()):
                     logger.info(f"  {key} = {value}")
                     writer.write(f"{key} = {value}\n")
 

examples/language-modeling/run_plm.py

@@ -93,6 +93,12 @@ class DataTrainingArguments:
     overwrite_cache: bool = field(
         default=False, metadata={"help": "Overwrite the cached training and evaluation sets"}
     )
+    validation_split_percentage: Optional[int] = field(
+        default=5,
+        metadata={
+            "help": "The percentage of the train set used as validation set in case there's no validation split"
+        },
+    )
     max_seq_length: int = field(
         default=512,
         metadata={
@@ -196,6 +202,17 @@ def main():
     if data_args.dataset_name is not None:
         # Downloading and loading a dataset from the hub.
         datasets = load_dataset(data_args.dataset_name, data_args.dataset_config_name)
+        if "validation" not in datasets.keys():
+            datasets["validation"] = load_dataset(
+                data_args.dataset_name,
+                data_args.dataset_config_name,
+                split=f"train[:{data_args.validation_split_percentage}%]",
+            )
+            datasets["train"] = load_dataset(
+                data_args.dataset_name,
+                data_args.dataset_config_name,
+                split=f"train[{data_args.validation_split_percentage}%:]",
+            )
     else:
         data_files = {}
         if data_args.train_file is not None:
@@ -346,9 +363,20 @@ def main():
             if (model_args.model_name_or_path is not None and os.path.isdir(model_args.model_name_or_path))
             else None
         )
-        trainer.train(model_path=model_path)
+        train_result = trainer.train(model_path=model_path)
         trainer.save_model()  # Saves the tokenizer too for easy upload
 
+        output_train_file = os.path.join(training_args.output_dir, "train_results.txt")
+        if trainer.is_world_process_zero():
+            with open(output_train_file, "w") as writer:
+                logger.info("***** Train results *****")
+                for key, value in sorted(train_result.metrics.items()):
+                    logger.info(f"  {key} = {value}")
+                    writer.write(f"{key} = {value}\n")
+
+            # Need to save the state, since Trainer.save_model saves only the tokenizer with the model
+            trainer.state.save_to_json(os.path.join(training_args.output_dir, "trainer_state.json"))
+
     # Evaluation
     results = {}
     if training_args.do_eval:
@@ -363,7 +391,7 @@ def main():
         if trainer.is_world_process_zero():
             with open(output_eval_file, "w") as writer:
                 logger.info("***** Eval results *****")
-                for key, value in results.items():
+                for key, value in sorted(results.items()):
                     logger.info(f"  {key} = {value}")
                     writer.write(f"{key} = {value}\n")
 

examples/legacy/README.md

@@ -0,0 +1,21 @@
+<!---
+Copyright 2020 The HuggingFace Team. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+-->
+
+# Legacy examples
+
+This folder contains examples which are not actively maintained (mostly contributed by the community).
+
+Using these examples together with a recent version of the library usually requires to make small (sometimes big) adaptations to get the scripts working.

examples/legacy/multiple_choice/utils_multiple_choice.py

@@ -0,0 +1,579 @@
+# coding=utf-8
+# Copyright 2018 The Google AI Language Team Authors and The HuggingFace Inc. team.
+# Copyright (c) 2018, NVIDIA CORPORATION.  All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+""" Multiple choice fine-tuning: utilities to work with multiple choice tasks of reading comprehension """
+
+
+import csv
+import glob
+import json
+import logging
+import os
+from dataclasses import dataclass
+from enum import Enum
+from typing import List, Optional
+
+import tqdm
+
+from filelock import FileLock
+from transformers import PreTrainedTokenizer, is_tf_available, is_torch_available
+
+
+logger = logging.getLogger(__name__)
+
+
+@dataclass(frozen=True)
+class InputExample:
+    """
+    A single training/test example for multiple choice
+
+    Args:
+        example_id: Unique id for the example.
+        question: string. The untokenized text of the second sequence (question).
+        contexts: list of str. The untokenized text of the first sequence (context of corresponding question).
+        endings: list of str. multiple choice's options. Its length must be equal to contexts' length.
+        label: (Optional) string. The label of the example. This should be
+        specified for train and dev examples, but not for test examples.
+    """
+
+    example_id: str
+    question: str
+    contexts: List[str]
+    endings: List[str]
+    label: Optional[str]
+
+
+@dataclass(frozen=True)
+class InputFeatures:
+    """
+    A single set of features of data.
+    Property names are the same names as the corresponding inputs to a model.
+    """
+
+    example_id: str
+    input_ids: List[List[int]]
+    attention_mask: Optional[List[List[int]]]
+    token_type_ids: Optional[List[List[int]]]
+    label: Optional[int]
+
+
+class Split(Enum):
+    train = "train"
+    dev = "dev"
+    test = "test"
+
+
+if is_torch_available():
+    import torch
+    from torch.utils.data.dataset import Dataset
+
+    class MultipleChoiceDataset(Dataset):
+        """
+        This will be superseded by a framework-agnostic approach
+        soon.
+        """
+
+        features: List[InputFeatures]
+
+        def __init__(
+            self,
+            data_dir: str,
+            tokenizer: PreTrainedTokenizer,
+            task: str,
+            max_seq_length: Optional[int] = None,
+            overwrite_cache=False,
+            mode: Split = Split.train,
+        ):
+            processor = processors[task]()
+
+            cached_features_file = os.path.join(
+                data_dir,
+                "cached_{}_{}_{}_{}".format(
+                    mode.value,
+                    tokenizer.__class__.__name__,
+                    str(max_seq_length),
+                    task,
+                ),
+            )
+
+            # Make sure only the first process in distributed training processes the dataset,
+            # and the others will use the cache.
+            lock_path = cached_features_file + ".lock"
+            with FileLock(lock_path):
+
+                if os.path.exists(cached_features_file) and not overwrite_cache:
+                    logger.info(f"Loading features from cached file {cached_features_file}")
+                    self.features = torch.load(cached_features_file)
+                else:
+                    logger.info(f"Creating features from dataset file at {data_dir}")
+                    label_list = processor.get_labels()
+                    if mode == Split.dev:
+                        examples = processor.get_dev_examples(data_dir)
+                    elif mode == Split.test:
+                        examples = processor.get_test_examples(data_dir)
+                    else:
+                        examples = processor.get_train_examples(data_dir)
+                    logger.info("Training examples: %s", len(examples))
+                    self.features = convert_examples_to_features(
+                        examples,
+                        label_list,
+                        max_seq_length,
+                        tokenizer,
+                    )
+                    logger.info("Saving features into cached file %s", cached_features_file)
+                    torch.save(self.features, cached_features_file)
+
+        def __len__(self):
+            return len(self.features)
+
+        def __getitem__(self, i) -> InputFeatures:
+            return self.features[i]
+
+
+if is_tf_available():
+    import tensorflow as tf
+
+    class TFMultipleChoiceDataset:
+        """
+        This will be superseded by a framework-agnostic approach
+        soon.
+        """
+
+        features: List[InputFeatures]
+
+        def __init__(
+            self,
+            data_dir: str,
+            tokenizer: PreTrainedTokenizer,
+            task: str,
+            max_seq_length: Optional[int] = 128,
+            overwrite_cache=False,
+            mode: Split = Split.train,
+        ):
+            processor = processors[task]()
+
+            logger.info(f"Creating features from dataset file at {data_dir}")
+            label_list = processor.get_labels()
+            if mode == Split.dev:
+                examples = processor.get_dev_examples(data_dir)
+            elif mode == Split.test:
+                examples = processor.get_test_examples(data_dir)
+            else:
+                examples = processor.get_train_examples(data_dir)
+            logger.info("Training examples: %s", len(examples))
+
+            self.features = convert_examples_to_features(
+                examples,
+                label_list,
+                max_seq_length,
+                tokenizer,
+            )
+
+            def gen():
+                for (ex_index, ex) in tqdm.tqdm(enumerate(self.features), desc="convert examples to features"):
+                    if ex_index % 10000 == 0:
+                        logger.info("Writing example %d of %d" % (ex_index, len(examples)))
+
+                    yield (
+                        {
+                            "example_id": 0,
+                            "input_ids": ex.input_ids,
+                            "attention_mask": ex.attention_mask,
+                            "token_type_ids": ex.token_type_ids,
+                        },
+                        ex.label,
+                    )
+
+            self.dataset = tf.data.Dataset.from_generator(
+                gen,
+                (
+                    {
+                        "example_id": tf.int32,
+                        "input_ids": tf.int32,
+                        "attention_mask": tf.int32,
+                        "token_type_ids": tf.int32,
+                    },
+                    tf.int64,
+                ),
+                (
+                    {
+                        "example_id": tf.TensorShape([]),
+                        "input_ids": tf.TensorShape([None, None]),
+                        "attention_mask": tf.TensorShape([None, None]),
+                        "token_type_ids": tf.TensorShape([None, None]),
+                    },
+                    tf.TensorShape([]),
+                ),
+            )
+
+        def get_dataset(self):
+            self.dataset = self.dataset.apply(tf.data.experimental.assert_cardinality(len(self.features)))
+
+            return self.dataset
+
+        def __len__(self):
+            return len(self.features)
+
+        def __getitem__(self, i) -> InputFeatures:
+            return self.features[i]
+
+
+class DataProcessor:
+    """Base class for data converters for multiple choice data sets."""
+
+    def get_train_examples(self, data_dir):
+        """Gets a collection of `InputExample`s for the train set."""
+        raise NotImplementedError()
+
+    def get_dev_examples(self, data_dir):
+        """Gets a collection of `InputExample`s for the dev set."""
+        raise NotImplementedError()
+
+    def get_test_examples(self, data_dir):
+        """Gets a collection of `InputExample`s for the test set."""
+        raise NotImplementedError()
+
+    def get_labels(self):
+        """Gets the list of labels for this data set."""
+        raise NotImplementedError()
+
+
+class RaceProcessor(DataProcessor):
+    """Processor for the RACE data set."""
+
+    def get_train_examples(self, data_dir):
+        """See base class."""
+        logger.info("LOOKING AT {} train".format(data_dir))
+        high = os.path.join(data_dir, "train/high")
+        middle = os.path.join(data_dir, "train/middle")
+        high = self._read_txt(high)
+        middle = self._read_txt(middle)
+        return self._create_examples(high + middle, "train")
+
+    def get_dev_examples(self, data_dir):
+        """See base class."""
+        logger.info("LOOKING AT {} dev".format(data_dir))
+        high = os.path.join(data_dir, "dev/high")
+        middle = os.path.join(data_dir, "dev/middle")
+        high = self._read_txt(high)
+        middle = self._read_txt(middle)
+        return self._create_examples(high + middle, "dev")
+
+    def get_test_examples(self, data_dir):
+        """See base class."""
+        logger.info("LOOKING AT {} test".format(data_dir))
+        high = os.path.join(data_dir, "test/high")
+        middle = os.path.join(data_dir, "test/middle")
+        high = self._read_txt(high)
+        middle = self._read_txt(middle)
+        return self._create_examples(high + middle, "test")
+
+    def get_labels(self):
+        """See base class."""
+        return ["0", "1", "2", "3"]
+
+    def _read_txt(self, input_dir):
+        lines = []
+        files = glob.glob(input_dir + "/*txt")
+        for file in tqdm.tqdm(files, desc="read files"):
+            with open(file, "r", encoding="utf-8") as fin:
+                data_raw = json.load(fin)
+                data_raw["race_id"] = file
+                lines.append(data_raw)
+        return lines
+
+    def _create_examples(self, lines, set_type):
+        """Creates examples for the training and dev sets."""
+        examples = []
+        for (_, data_raw) in enumerate(lines):
+            race_id = "%s-%s" % (set_type, data_raw["race_id"])
+            article = data_raw["article"]
+            for i in range(len(data_raw["answers"])):
+                truth = str(ord(data_raw["answers"][i]) - ord("A"))
+                question = data_raw["questions"][i]
+                options = data_raw["options"][i]
+
+                examples.append(
+                    InputExample(
+                        example_id=race_id,
+                        question=question,
+                        contexts=[article, article, article, article],  # this is not efficient but convenient
+                        endings=[options[0], options[1], options[2], options[3]],
+                        label=truth,
+                    )
+                )
+        return examples
+
+
+class SynonymProcessor(DataProcessor):
+    """Processor for the Synonym data set."""
+
+    def get_train_examples(self, data_dir):
+        """See base class."""
+        logger.info("LOOKING AT {} train".format(data_dir))
+        return self._create_examples(self._read_csv(os.path.join(data_dir, "mctrain.csv")), "train")
+
+    def get_dev_examples(self, data_dir):
+        """See base class."""
+        logger.info("LOOKING AT {} dev".format(data_dir))
+        return self._create_examples(self._read_csv(os.path.join(data_dir, "mchp.csv")), "dev")
+
+    def get_test_examples(self, data_dir):
+        """See base class."""
+        logger.info("LOOKING AT {} dev".format(data_dir))
+
+        return self._create_examples(self._read_csv(os.path.join(data_dir, "mctest.csv")), "test")
+
+    def get_labels(self):
+        """See base class."""
+        return ["0", "1", "2", "3", "4"]
+
+    def _read_csv(self, input_file):
+        with open(input_file, "r", encoding="utf-8") as f:
+            return list(csv.reader(f))
+
+    def _create_examples(self, lines: List[List[str]], type: str):
+        """Creates examples for the training and dev sets."""
+
+        examples = [
+            InputExample(
+                example_id=line[0],
+                question="",  # in the swag dataset, the
+                # common beginning of each
+                # choice is stored in "sent2".
+                contexts=[line[1], line[1], line[1], line[1], line[1]],
+                endings=[line[2], line[3], line[4], line[5], line[6]],
+                label=line[7],
+            )
+            for line in lines  # we skip the line with the column names
+        ]
+
+        return examples
+
+
+class SwagProcessor(DataProcessor):
+    """Processor for the SWAG data set."""
+
+    def get_train_examples(self, data_dir):
+        """See base class."""
+        logger.info("LOOKING AT {} train".format(data_dir))
+        return self._create_examples(self._read_csv(os.path.join(data_dir, "train.csv")), "train")
+
+    def get_dev_examples(self, data_dir):
+        """See base class."""
+        logger.info("LOOKING AT {} dev".format(data_dir))
+        return self._create_examples(self._read_csv(os.path.join(data_dir, "val.csv")), "dev")
+
+    def get_test_examples(self, data_dir):
+        """See base class."""
+        logger.info("LOOKING AT {} dev".format(data_dir))
+        raise ValueError(
+            "For swag testing, the input file does not contain a label column. It can not be tested in current code"
+            "setting!"
+        )
+        return self._create_examples(self._read_csv(os.path.join(data_dir, "test.csv")), "test")
+
+    def get_labels(self):
+        """See base class."""
+        return ["0", "1", "2", "3"]
+
+    def _read_csv(self, input_file):
+        with open(input_file, "r", encoding="utf-8") as f:
+            return list(csv.reader(f))
+
+    def _create_examples(self, lines: List[List[str]], type: str):
+        """Creates examples for the training and dev sets."""
+        if type == "train" and lines[0][-1] != "label":
+            raise ValueError("For training, the input file must contain a label column.")
+
+        examples = [
+            InputExample(
+                example_id=line[2],
+                question=line[5],  # in the swag dataset, the
+                # common beginning of each
+                # choice is stored in "sent2".
+                contexts=[line[4], line[4], line[4], line[4]],
+                endings=[line[7], line[8], line[9], line[10]],
+                label=line[11],
+            )
+            for line in lines[1:]  # we skip the line with the column names
+        ]
+
+        return examples
+
+
+class ArcProcessor(DataProcessor):
+    """Processor for the ARC data set (request from allennlp)."""
+
+    def get_train_examples(self, data_dir):
+        """See base class."""
+        logger.info("LOOKING AT {} train".format(data_dir))
+        return self._create_examples(self._read_json(os.path.join(data_dir, "train.jsonl")), "train")
+
+    def get_dev_examples(self, data_dir):
+        """See base class."""
+        logger.info("LOOKING AT {} dev".format(data_dir))
+        return self._create_examples(self._read_json(os.path.join(data_dir, "dev.jsonl")), "dev")
+
+    def get_test_examples(self, data_dir):
+        logger.info("LOOKING AT {} test".format(data_dir))
+        return self._create_examples(self._read_json(os.path.join(data_dir, "test.jsonl")), "test")
+
+    def get_labels(self):
+        """See base class."""
+        return ["0", "1", "2", "3"]
+
+    def _read_json(self, input_file):
+        with open(input_file, "r", encoding="utf-8") as fin:
+            lines = fin.readlines()
+            return lines
+
+    def _create_examples(self, lines, type):
+        """Creates examples for the training and dev sets."""
+
+        # There are two types of labels. They should be normalized
+        def normalize(truth):
+            if truth in "ABCD":
+                return ord(truth) - ord("A")
+            elif truth in "1234":
+                return int(truth) - 1
+            else:
+                logger.info("truth ERROR! %s", str(truth))
+                return None
+
+        examples = []
+        three_choice = 0
+        four_choice = 0
+        five_choice = 0
+        other_choices = 0
+        # we deleted example which has more than or less than four choices
+        for line in tqdm.tqdm(lines, desc="read arc data"):
+            data_raw = json.loads(line.strip("\n"))
+            if len(data_raw["question"]["choices"]) == 3:
+                three_choice += 1
+                continue
+            elif len(data_raw["question"]["choices"]) == 5:
+                five_choice += 1
+                continue
+            elif len(data_raw["question"]["choices"]) != 4:
+                other_choices += 1
+                continue
+            four_choice += 1
+            truth = str(normalize(data_raw["answerKey"]))
+            assert truth != "None"
+            question_choices = data_raw["question"]
+            question = question_choices["stem"]
+            id = data_raw["id"]
+            options = question_choices["choices"]
+            if len(options) == 4:
+                examples.append(
+                    InputExample(
+                        example_id=id,
+                        question=question,
+                        contexts=[
+                            options[0]["para"].replace("_", ""),
+                            options[1]["para"].replace("_", ""),
+                            options[2]["para"].replace("_", ""),
+                            options[3]["para"].replace("_", ""),
+                        ],
+                        endings=[options[0]["text"], options[1]["text"], options[2]["text"], options[3]["text"]],
+                        label=truth,
+                    )
+                )
+
+        if type == "train":
+            assert len(examples) > 1
+            assert examples[0].label is not None
+        logger.info("len examples: %s}", str(len(examples)))
+        logger.info("Three choices: %s", str(three_choice))
+        logger.info("Five choices: %s", str(five_choice))
+        logger.info("Other choices: %s", str(other_choices))
+        logger.info("four choices: %s", str(four_choice))
+
+        return examples
+
+
+def convert_examples_to_features(
+    examples: List[InputExample],
+    label_list: List[str],
+    max_length: int,
+    tokenizer: PreTrainedTokenizer,
+) -> List[InputFeatures]:
+    """
+    Loads a data file into a list of `InputFeatures`
+    """
+
+    label_map = {label: i for i, label in enumerate(label_list)}
+
+    features = []
+    for (ex_index, example) in tqdm.tqdm(enumerate(examples), desc="convert examples to features"):
+        if ex_index % 10000 == 0:
+            logger.info("Writing example %d of %d" % (ex_index, len(examples)))
+        choices_inputs = []
+        for ending_idx, (context, ending) in enumerate(zip(example.contexts, example.endings)):
+            text_a = context
+            if example.question.find("_") != -1:
+                # this is for cloze question
+                text_b = example.question.replace("_", ending)
+            else:
+                text_b = example.question + " " + ending
+
+            inputs = tokenizer(
+                text_a,
+                text_b,
+                add_special_tokens=True,
+                max_length=max_length,
+                padding="max_length",
+                truncation=True,
+                return_overflowing_tokens=True,
+            )
+            if "num_truncated_tokens" in inputs and inputs["num_truncated_tokens"] > 0:
+                logger.info(
+                    "Attention! you are cropping tokens (swag task is ok). "
+                    "If you are training ARC and RACE and you are poping question + options,"
+                    "you need to try to use a bigger max seq length!"
+                )
+
+            choices_inputs.append(inputs)
+
+        label = label_map[example.label]
+
+        input_ids = [x["input_ids"] for x in choices_inputs]
+        attention_mask = (
+            [x["attention_mask"] for x in choices_inputs] if "attention_mask" in choices_inputs[0] else None
+        )
+        token_type_ids = (
+            [x["token_type_ids"] for x in choices_inputs] if "token_type_ids" in choices_inputs[0] else None
+        )
+
+        features.append(
+            InputFeatures(
+                example_id=example.example_id,
+                input_ids=input_ids,
+                attention_mask=attention_mask,
+                token_type_ids=token_type_ids,
+                label=label,
+            )
+        )
+
+    for f in features[:2]:
+        logger.info("*** Example ***")
+        logger.info("feature: %s" % f)
+
+    return features
+
+
+processors = {"race": RaceProcessor, "swag": SwagProcessor, "arc": ArcProcessor, "syn": SynonymProcessor}
+MULTIPLE_CHOICE_TASKS_NUM_LABELS = {"race", 4, "swag", 4, "arc", 4, "syn", 5}

examples/legacy/pytorch-lightning/requirements.txt

@@ -19,3 +19,4 @@ pytest
 conllu
 sentencepiece != 0.1.92
 protobuf
+ray

examples/legacy/pytorch-lightning/run_glue.sh

@@ -21,7 +21,7 @@ mkdir -p $OUTPUT_DIR
 # Add parent directory to python path to access lightning_base.py
 export PYTHONPATH="../":"${PYTHONPATH}"
 
-python3 run_pl_glue.py --gpus 1 --data_dir $DATA_DIR \
+python3 run_glue.py --gpus 1 --data_dir $DATA_DIR \
 --task $TASK \
 --model_name_or_path $BERT_MODEL \
 --output_dir $OUTPUT_DIR \

examples/legacy/pytorch-lightning/run_ner.sh

@@ -31,7 +31,7 @@ mkdir -p $OUTPUT_DIR
 # Add parent directory to python path to access lightning_base.py
 export PYTHONPATH="../":"${PYTHONPATH}"
 
-python3 run_pl_ner.py --data_dir ./ \
+python3 run_ner.py --data_dir ./ \
 --labels ./labels.txt \
 --model_name_or_path $BERT_MODEL \
 --output_dir $OUTPUT_DIR \

examples/legacy/pytorch-lightning/run_pos.sh

@@ -26,7 +26,7 @@ export SEED=1
 # Add parent directory to python path to access lightning_base.py
 export PYTHONPATH="../":"${PYTHONPATH}"
 
-python3 run_pl_ner.py --data_dir ./ \
+python3 run_ner.py --data_dir ./ \
 --task_type POS \
 --model_name_or_path $BERT_MODEL \
 --output_dir $OUTPUT_DIR \

examples/legacy/token-classification/README.md

@@ -0,0 +1,229 @@
+## Token classification
+
+Based on the scripts [`run_ner.py`](https://github.com/huggingface/transformers/blob/master/examples/contrib/legacy/token-classification/run_ner.py).
+
+The following examples are covered in this section:
+
+* NER on the GermEval 2014 (German NER) dataset
+* Emerging and Rare Entities task: WNUT’17 (English NER) dataset
+
+Details and results for the fine-tuning provided by @stefan-it.
+
+### GermEval 2014 (German NER) dataset
+
+#### Data (Download and pre-processing steps)
+
+Data can be obtained from the [GermEval 2014](https://sites.google.com/site/germeval2014ner/data) shared task page.
+
+Here are the commands for downloading and pre-processing train, dev and test datasets. The original data format has four (tab-separated) columns, in a pre-processing step only the two relevant columns (token and outer span NER annotation) are extracted:
+
+```bash
+curl -L 'https://drive.google.com/uc?export=download&id=1Jjhbal535VVz2ap4v4r_rN1UEHTdLK5P' \
+| grep -v "^#" | cut -f 2,3 | tr '\t' ' ' > train.txt.tmp
+curl -L 'https://drive.google.com/uc?export=download&id=1ZfRcQThdtAR5PPRjIDtrVP7BtXSCUBbm' \
+| grep -v "^#" | cut -f 2,3 | tr '\t' ' ' > dev.txt.tmp
+curl -L 'https://drive.google.com/uc?export=download&id=1u9mb7kNJHWQCWyweMDRMuTFoOHOfeBTH' \
+| grep -v "^#" | cut -f 2,3 | tr '\t' ' ' > test.txt.tmp
+```
+
+The GermEval 2014 dataset contains some strange "control character" tokens like `'\x96', '\u200e', '\x95', '\xad' or '\x80'`.
+One problem with these tokens is, that `BertTokenizer` returns an empty token for them, resulting in misaligned `InputExample`s.
+The `preprocess.py` script located in the `scripts` folder a) filters these tokens and b) splits longer sentences into smaller ones (once the max. subtoken length is reached).
+
+Let's define some variables that we need for further pre-processing steps and training the model:
+
+```bash
+export MAX_LENGTH=128
+export BERT_MODEL=bert-base-multilingual-cased
+```
+
+Run the pre-processing script on training, dev and test datasets:
+
+```bash
+python3 scripts/preprocess.py train.txt.tmp $BERT_MODEL $MAX_LENGTH > train.txt
+python3 scripts/preprocess.py dev.txt.tmp $BERT_MODEL $MAX_LENGTH > dev.txt
+python3 scripts/preprocess.py test.txt.tmp $BERT_MODEL $MAX_LENGTH > test.txt
+```
+
+The GermEval 2014 dataset has much more labels than CoNLL-2002/2003 datasets, so an own set of labels must be used:
+
+```bash
+cat train.txt dev.txt test.txt | cut -d " " -f 2 | grep -v "^$"| sort | uniq > labels.txt
+```
+
+#### Prepare the run
+
+Additional environment variables must be set:
+
+```bash
+export OUTPUT_DIR=germeval-model
+export BATCH_SIZE=32
+export NUM_EPOCHS=3
+export SAVE_STEPS=750
+export SEED=1
+```
+
+#### Run the Pytorch version
+
+To start training, just run:
+
+```bash
+python3 run_ner.py --data_dir ./ \
+--labels ./labels.txt \
+--model_name_or_path $BERT_MODEL \
+--output_dir $OUTPUT_DIR \
+--max_seq_length  $MAX_LENGTH \
+--num_train_epochs $NUM_EPOCHS \
+--per_device_train_batch_size $BATCH_SIZE \
+--save_steps $SAVE_STEPS \
+--seed $SEED \
+--do_train \
+--do_eval \
+--do_predict
+```
+
+If your GPU supports half-precision training, just add the `--fp16` flag. After training, the model will be both evaluated on development and test datasets.
+
+#### JSON-based configuration file
+
+Instead of passing all parameters via commandline arguments, the `run_ner.py` script also supports reading parameters from a json-based configuration file:
+
+```json
+{
+    "data_dir": ".",
+    "labels": "./labels.txt",
+    "model_name_or_path": "bert-base-multilingual-cased",
+    "output_dir": "germeval-model",
+    "max_seq_length": 128,
+    "num_train_epochs": 3,
+    "per_device_train_batch_size": 32,
+    "save_steps": 750,
+    "seed": 1,
+    "do_train": true,
+    "do_eval": true,
+    "do_predict": true
+}
+```
+
+It must be saved with a `.json` extension and can be used by running `python3 run_ner.py config.json`.
+
+#### Evaluation
+
+Evaluation on development dataset outputs the following for our example:
+
+```bash
+10/04/2019 00:42:06 - INFO - __main__ -   ***** Eval results  *****
+10/04/2019 00:42:06 - INFO - __main__ -     f1 = 0.8623348017621146
+10/04/2019 00:42:06 - INFO - __main__ -     loss = 0.07183869666975543
+10/04/2019 00:42:06 - INFO - __main__ -     precision = 0.8467916366258111
+10/04/2019 00:42:06 - INFO - __main__ -     recall = 0.8784592370979806
+```
+
+On the test dataset the following results could be achieved:
+
+```bash
+10/04/2019 00:42:42 - INFO - __main__ -   ***** Eval results  *****
+10/04/2019 00:42:42 - INFO - __main__ -     f1 = 0.8614389652384803
+10/04/2019 00:42:42 - INFO - __main__ -     loss = 0.07064602487454782
+10/04/2019 00:42:42 - INFO - __main__ -     precision = 0.8604651162790697
+10/04/2019 00:42:42 - INFO - __main__ -     recall = 0.8624150210424085
+```
+
+### Emerging and Rare Entities task: WNUT’17 (English NER) dataset
+
+Description of the WNUT’17 task from the [shared task website](http://noisy-text.github.io/2017/index.html):
+
+> The WNUT’17 shared task focuses on identifying unusual, previously-unseen entities in the context of emerging discussions.
+> Named entities form the basis of many modern approaches to other tasks (like event clustering and summarization), but recall on
+> them is a real problem in noisy text - even among annotators. This drop tends to be due to novel entities and surface forms.
+
+Six labels are available in the dataset. An overview can be found on this [page](http://noisy-text.github.io/2017/files/).
+
+#### Data (Download and pre-processing steps)
+
+The dataset can be downloaded from the [official GitHub](https://github.com/leondz/emerging_entities_17) repository.
+
+The following commands show how to prepare the dataset for fine-tuning:
+
+```bash
+mkdir -p data_wnut_17
+
+curl -L 'https://github.com/leondz/emerging_entities_17/raw/master/wnut17train.conll'  | tr '\t' ' ' > data_wnut_17/train.txt.tmp
+curl -L 'https://github.com/leondz/emerging_entities_17/raw/master/emerging.dev.conll' | tr '\t' ' ' > data_wnut_17/dev.txt.tmp
+curl -L 'https://raw.githubusercontent.com/leondz/emerging_entities_17/master/emerging.test.annotated' | tr '\t' ' ' > data_wnut_17/test.txt.tmp
+```
+
+Let's define some variables that we need for further pre-processing steps:
+
+```bash
+export MAX_LENGTH=128
+export BERT_MODEL=bert-large-cased
+```
+
+Here we use the English BERT large model for fine-tuning.
+The `preprocess.py` scripts splits longer sentences into smaller ones (once the max. subtoken length is reached):
+
+```bash
+python3 scripts/preprocess.py data_wnut_17/train.txt.tmp $BERT_MODEL $MAX_LENGTH > data_wnut_17/train.txt
+python3 scripts/preprocess.py data_wnut_17/dev.txt.tmp $BERT_MODEL $MAX_LENGTH > data_wnut_17/dev.txt
+python3 scripts/preprocess.py data_wnut_17/test.txt.tmp $BERT_MODEL $MAX_LENGTH > data_wnut_17/test.txt
+```
+
+In the last pre-processing step, the `labels.txt` file needs to be generated. This file contains all available labels:
+
+```bash
+cat data_wnut_17/train.txt data_wnut_17/dev.txt data_wnut_17/test.txt | cut -d " " -f 2 | grep -v "^$"| sort | uniq > data_wnut_17/labels.txt
+```
+
+#### Run the Pytorch version
+
+Fine-tuning with the PyTorch version can be started using the `run_ner.py` script. In this example we use a JSON-based configuration file.
+
+This configuration file looks like:
+
+```json
+{
+    "data_dir": "./data_wnut_17",
+    "labels": "./data_wnut_17/labels.txt",
+    "model_name_or_path": "bert-large-cased",
+    "output_dir": "wnut-17-model-1",
+    "max_seq_length": 128,
+    "num_train_epochs": 3,
+    "per_device_train_batch_size": 32,
+    "save_steps": 425,
+    "seed": 1,
+    "do_train": true,
+    "do_eval": true,
+    "do_predict": true,
+    "fp16": false
+}
+```
+
+If your GPU supports half-precision training, please set `fp16` to `true`.
+
+Save this JSON-based configuration under `wnut_17.json`. The fine-tuning can be started with `python3 run_ner_old.py wnut_17.json`.
+
+#### Evaluation
+
+Evaluation on development dataset outputs the following:
+
+```bash
+05/29/2020 23:33:44 - INFO - __main__ -   ***** Eval results *****
+05/29/2020 23:33:44 - INFO - __main__ -     eval_loss = 0.26505235286212275
+05/29/2020 23:33:44 - INFO - __main__ -     eval_precision = 0.7008264462809918
+05/29/2020 23:33:44 - INFO - __main__ -     eval_recall = 0.507177033492823
+05/29/2020 23:33:44 - INFO - __main__ -     eval_f1 = 0.5884802220680084
+05/29/2020 23:33:44 - INFO - __main__ -     epoch = 3.0
+```
+
+On the test dataset the following results could be achieved:
+
+```bash
+05/29/2020 23:33:44 - INFO - transformers.trainer -   ***** Running Prediction *****
+05/29/2020 23:34:02 - INFO - __main__ -     eval_loss = 0.30948806500973547
+05/29/2020 23:34:02 - INFO - __main__ -     eval_precision = 0.5840108401084011
+05/29/2020 23:34:02 - INFO - __main__ -     eval_recall = 0.3994439295644115
+05/29/2020 23:34:02 - INFO - __main__ -     eval_f1 = 0.47440836543753434
+```
+
+WNUT’17 is a very difficult task. Current state-of-the-art results on this dataset can be found [here](http://nlpprogress.com/english/named_entity_recognition.html).

examples/legacy/token-classification/run.sh

@@ -20,7 +20,7 @@ export NUM_EPOCHS=3
 export SAVE_STEPS=750
 export SEED=1
 
-python3 run_ner_old.py \
+python3 run_ner.py \
 --task_type NER \
 --data_dir . \
 --labels ./labels.txt \

examples/legacy/token-classification/run_chunk.sh

@@ -21,7 +21,7 @@ export NUM_EPOCHS=3
 export SAVE_STEPS=750
 export SEED=1
 
-python3 run_ner_old.py \
+python3 run_ner.py \
 --task_type Chunk \
 --data_dir . \
 --model_name_or_path $BERT_MODEL \

examples/legacy/token-classification/run_pos.sh

@@ -21,7 +21,7 @@ export NUM_EPOCHS=3
 export SAVE_STEPS=750
 export SEED=1
 
-python3 run_ner_old.py \
+python3 run_ner.py \
 --task_type POS \
 --data_dir . \
 --model_name_or_path $BERT_MODEL \

examples/multiple-choice/README.md

@@ -1,26 +1,35 @@
+<!---
+Copyright 2020 The HuggingFace Team. All rights reserved.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+-->
+
 ## Multiple Choice
 
-Based on the script [`run_multiple_choice.py`]().
+Based on the script [`run_swag.py`]().
 
 #### Fine-tuning on SWAG
-Download [swag](https://github.com/rowanz/swagaf/tree/master/data) data
 
 ```bash
-#training on 4 tesla V100(16GB) GPUS
-export SWAG_DIR=/path/to/swag_data_dir
-python ./examples/multiple-choice/run_multiple_choice.py \
---task_name swag \
+python examples/multiple-choice/run_swag.py \
 --model_name_or_path roberta-base \
 --do_train \
 --do_eval \
---data_dir $SWAG_DIR \
 --learning_rate 5e-5 \
 --num_train_epochs 3 \
---max_seq_length 80 \
---output_dir models_bert/swag_base \
+--output_dir /tmp/swag_base \
 --per_gpu_eval_batch_size=16 \
 --per_device_train_batch_size=16 \
---gradient_accumulation_steps 2 \
 --overwrite_output
 ```
 Training with the defined hyper-parameters yields the following results:

examples/multiple-choice/requirements.txt

@@ -0,0 +1,2 @@
+sentencepiece != 0.1.92
+protobuf

examples/multiple-choice/run_swag.py

@@ -0,0 +1,360 @@
+# coding=utf-8
+# Copyright The HuggingFace Team and The HuggingFace Inc. team. All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""
+Fine-tuning the library models for multiple choice.
+"""
+# You can also adapt this script on your own multiple choice task. Pointers for this are left as comments.
+
+import logging
+import os
+import sys
+from dataclasses import dataclass, field
+from typing import Optional, Union
+
+import numpy as np
+import torch
+from datasets import load_dataset
+
+import transformers
+from transformers import (
+    AutoConfig,
+    AutoModelForMultipleChoice,
+    AutoTokenizer,
+    HfArgumentParser,
+    Trainer,
+    TrainingArguments,
+    default_data_collator,
+    set_seed,
+)
+from transformers.tokenization_utils_base import PaddingStrategy, PreTrainedTokenizerBase
+from transformers.trainer_utils import is_main_process
+
+
+logger = logging.getLogger(__name__)
+
+
+@dataclass
+class ModelArguments:
+    """
+    Arguments pertaining to which model/config/tokenizer we are going to fine-tune from.
+    """
+
+    model_name_or_path: str = field(
+        metadata={"help": "Path to pretrained model or model identifier from huggingface.co/models"}
+    )
+    config_name: Optional[str] = field(
+        default=None, metadata={"help": "Pretrained config name or path if not the same as model_name"}
+    )
+    tokenizer_name: Optional[str] = field(
+        default=None, metadata={"help": "Pretrained tokenizer name or path if not the same as model_name"}
+    )
+    cache_dir: Optional[str] = field(
+        default=None,
+        metadata={"help": "Where do you want to store the pretrained models downloaded from huggingface.co"},
+    )
+    use_fast_tokenizer: bool = field(
+        default=True,
+        metadata={"help": "Whether to use one of the fast tokenizer (backed by the tokenizers library) or not."},
+    )
+
+
+@dataclass
+class DataTrainingArguments:
+    """
+    Arguments pertaining to what data we are going to input our model for training and eval.
+    """
+
+    train_file: Optional[str] = field(default=None, metadata={"help": "The input training data file (a text file)."})
+    validation_file: Optional[str] = field(
+        default=None,
+        metadata={"help": "An optional input evaluation data file to evaluate the perplexity on (a text file)."},
+    )
+    overwrite_cache: bool = field(
+        default=False, metadata={"help": "Overwrite the cached training and evaluation sets"}
+    )
+    preprocessing_num_workers: Optional[int] = field(
+        default=None,
+        metadata={"help": "The number of processes to use for the preprocessing."},
+    )
+    max_seq_length: int = field(
+        default=None,
+        metadata={
+            "help": "The maximum total input sequence length after tokenization. If passed, sequences longer "
+            "than this will be truncated, sequences shorter will be padded."
+        },
+    )
+    pad_to_max_length: bool = field(
+        default=False,
+        metadata={
+            "help": "Whether to pad all samples to the maximum sentence length. "
+            "If False, will pad the samples dynamically when batching to the maximum length in the batch. More "
+            "efficient on GPU but very bad for TPU."
+        },
+    )
+
+    def __post_init__(self):
+        if self.train_file is not None:
+            extension = self.train_file.split(".")[-1]
+            assert extension in ["csv", "json"], "`train_file` should be a csv or a json file."
+        if self.validation_file is not None:
+            extension = self.validation_file.split(".")[-1]
+            assert extension in ["csv", "json"], "`validation_file` should be a csv or a json file."
+
+
+@dataclass
+class DataCollatorForMultipleChoice:
+    """
+    Data collator that will dynamically pad the inputs for multiple choice received.
+
+    Args:
+        tokenizer (:class:`~transformers.PreTrainedTokenizer` or :class:`~transformers.PreTrainedTokenizerFast`):
+            The tokenizer used for encoding the data.
+        padding (:obj:`bool`, :obj:`str` or :class:`~transformers.tokenization_utils_base.PaddingStrategy`, `optional`, defaults to :obj:`True`):
+            Select a strategy to pad the returned sequences (according to the model's padding side and padding index)
+            among:
+
+            * :obj:`True` or :obj:`'longest'`: Pad to the longest sequence in the batch (or no padding if only a single
+              sequence if provided).
+            * :obj:`'max_length'`: Pad to a maximum length specified with the argument :obj:`max_length` or to the
+              maximum acceptable input length for the model if that argument is not provided.
+            * :obj:`False` or :obj:`'do_not_pad'` (default): No padding (i.e., can output a batch with sequences of
+              different lengths).
+        max_length (:obj:`int`, `optional`):
+            Maximum length of the returned list and optionally padding length (see above).
+        pad_to_multiple_of (:obj:`int`, `optional`):
+            If set will pad the sequence to a multiple of the provided value.
+
+            This is especially useful to enable the use of Tensor Cores on NVIDIA hardware with compute capability >=
+            7.5 (Volta).
+    """
+
+    tokenizer: PreTrainedTokenizerBase
+    padding: Union[bool, str, PaddingStrategy] = True
+    max_length: Optional[int] = None
+    pad_to_multiple_of: Optional[int] = None
+
+    def __call__(self, features):
+        label_name = "label" if "label" in features[0].keys() else "labels"
+        labels = [feature.pop(label_name) for feature in features]
+        batch_size = len(features)
+        num_choices = len(features[0]["input_ids"])
+        flattened_features = [
+            [{k: v[i] for k, v in feature.items()} for i in range(num_choices)] for feature in features
+        ]
+        flattened_features = sum(flattened_features, [])
+
+        batch = self.tokenizer.pad(
+            flattened_features,
+            padding=self.padding,
+            max_length=self.max_length,
+            pad_to_multiple_of=self.pad_to_multiple_of,
+            return_tensors="pt",
+        )
+
+        # Un-flatten
+        batch = {k: v.view(batch_size, num_choices, -1) for k, v in batch.items()}
+        # Add back labels
+        batch["labels"] = torch.tensor(labels, dtype=torch.int64)
+        return batch
+
+
+def main():
+    # See all possible arguments in src/transformers/training_args.py
+    # or by passing the --help flag to this script.
+    # We now keep distinct sets of args, for a cleaner separation of concerns.
+
+    parser = HfArgumentParser((ModelArguments, DataTrainingArguments, TrainingArguments))
+    if len(sys.argv) == 2 and sys.argv[1].endswith(".json"):
+        # If we pass only one argument to the script and it's the path to a json file,
+        # let's parse it to get our arguments.
+        model_args, data_args, training_args = parser.parse_json_file(json_file=os.path.abspath(sys.argv[1]))
+    else:
+        model_args, data_args, training_args = parser.parse_args_into_dataclasses()
+
+    if (
+        os.path.exists(training_args.output_dir)
+        and os.listdir(training_args.output_dir)
+        and training_args.do_train
+        and not training_args.overwrite_output_dir
+    ):
+        raise ValueError(
+            f"Output directory ({training_args.output_dir}) already exists and is not empty."
+            "Use --overwrite_output_dir to overcome."
+        )
+
+    # Setup logging
+    logging.basicConfig(
+        format="%(asctime)s - %(levelname)s - %(name)s -   %(message)s",
+        datefmt="%m/%d/%Y %H:%M:%S",
+        level=logging.INFO if is_main_process(training_args.local_rank) else logging.WARN,
+    )
+
+    # Log on each process the small summary:
+    logger.warning(
+        f"Process rank: {training_args.local_rank}, device: {training_args.device}, n_gpu: {training_args.n_gpu}"
+        + f"distributed training: {bool(training_args.local_rank != -1)}, 16-bits training: {training_args.fp16}"
+    )
+    # Set the verbosity to info of the Transformers logger (on main process only):
+    if is_main_process(training_args.local_rank):
+        transformers.utils.logging.set_verbosity_info()
+    logger.info("Training/evaluation parameters %s", training_args)
+
+    # Set seed before initializing model.
+    set_seed(training_args.seed)
+
+    # Get the datasets: you can either provide your own CSV/JSON/TXT training and evaluation files (see below)
+    # or just provide the name of one of the public datasets available on the hub at https://huggingface.co/datasets/
+    # (the dataset will be downloaded automatically from the datasets Hub).
+
+    # For CSV/JSON files, this script will use the column called 'text' or the first column if no column called
+    # 'text' is found. You can easily tweak this behavior (see below).
+
+    # In distributed training, the load_dataset function guarantee that only one local process can concurrently
+    # download the dataset.
+    if data_args.train_file is not None or data_args.validation_file is not None:
+        data_files = {}
+        if data_args.train_file is not None:
+            data_files["train"] = data_args.train_file
+        if data_args.validation_file is not None:
+            data_files["validation"] = data_args.validation_file
+        extension = data_args.train_file.split(".")[-1]
+        datasets = load_dataset(extension, data_files=data_files)
+    else:
+        # Downloading and loading the swag dataset from the hub.
+        datasets = load_dataset("swag", "regular")
+    # See more about loading any type of standard or custom dataset (from files, python dict, pandas DataFrame, etc) at
+    # https://huggingface.co/docs/datasets/loading_datasets.html.
+
+    # Load pretrained model and tokenizer
+
+    # Distributed training:
+    # The .from_pretrained methods guarantee that only one local process can concurrently
+    # download model & vocab.
+    config = AutoConfig.from_pretrained(
+        model_args.config_name if model_args.config_name else model_args.model_name_or_path,
+        cache_dir=model_args.cache_dir,
+    )
+    tokenizer = AutoTokenizer.from_pretrained(
+        model_args.tokenizer_name if model_args.tokenizer_name else model_args.model_name_or_path,
+        cache_dir=model_args.cache_dir,
+        use_fast=model_args.use_fast_tokenizer,
+    )
+    model = AutoModelForMultipleChoice.from_pretrained(
+        model_args.model_name_or_path,
+        from_tf=bool(".ckpt" in model_args.model_name_or_path),
+        config=config,
+        cache_dir=model_args.cache_dir,
+    )
+
+    # When using your own dataset or a different dataset from swag, you will probably need to change this.
+    ending_names = [f"ending{i}" for i in range(4)]
+    context_name = "sent1"
+    question_header_name = "sent2"
+
+    # Preprocessing the datasets.
+    def preprocess_function(examples):
+        first_sentences = [[context] * 4 for context in examples[context_name]]
+        question_headers = examples[question_header_name]
+        second_sentences = [
+            [f"{header} {examples[end][i]}" for end in ending_names] for i, header in enumerate(question_headers)
+        ]
+
+        # Flatten out
+        first_sentences = sum(first_sentences, [])
+        second_sentences = sum(second_sentences, [])
+
+        # Tokenize
+        tokenized_examples = tokenizer(
+            first_sentences,
+            second_sentences,
+            truncation=True,
+            max_length=data_args.max_seq_length,
+            padding="max_length" if data_args.pad_to_max_length else False,
+        )
+        # Un-flatten
+        return {k: [v[i : i + 4] for i in range(0, len(v), 4)] for k, v in tokenized_examples.items()}
+
+    tokenized_datasets = datasets.map(
+        preprocess_function,
+        batched=True,
+        num_proc=data_args.preprocessing_num_workers,
+        load_from_cache_file=not data_args.overwrite_cache,
+    )
+
+    # Data collator
+    data_collator = (
+        default_data_collator if data_args.pad_to_max_length else DataCollatorForMultipleChoice(tokenizer=tokenizer)
+    )
+
+    # Metric
+    def compute_metrics(eval_predictions):
+        predictions, label_ids = eval_predictions
+        preds = np.argmax(predictions, axis=1)
+        return {"accuracy": (preds == label_ids).astype(np.float32).mean().item()}
+
+    # Initialize our Trainer
+    trainer = Trainer(
+        model=model,
+        args=training_args,
+        train_dataset=tokenized_datasets["train"] if training_args.do_train else None,
+        eval_dataset=tokenized_datasets["validation"] if training_args.do_eval else None,
+        tokenizer=tokenizer,
+        data_collator=data_collator,
+        compute_metrics=compute_metrics,
+    )
+
+    # Training
+    if training_args.do_train:
+        train_result = trainer.train(
+            model_path=model_args.model_name_or_path if os.path.isdir(model_args.model_name_or_path) else None
+        )
+        trainer.save_model()  # Saves the tokenizer too for easy upload
+
+        output_train_file = os.path.join(training_args.output_dir, "train_results.txt")
+        if trainer.is_world_process_zero():
+            with open(output_train_file, "w") as writer:
+                logger.info("***** Train results *****")
+                for key, value in sorted(train_result.metrics.items()):
+                    logger.info(f"  {key} = {value}")
+                    writer.write(f"{key} = {value}\n")
+
+            # Need to save the state, since Trainer.save_model saves only the tokenizer with the model
+            trainer.state.save_to_json(os.path.join(training_args.output_dir, "trainer_state.json"))
+
+    # Evaluation
+    results = {}
+    if training_args.do_eval:
+        logger.info("*** Evaluate ***")
+
+        results = trainer.evaluate()
+
+        output_eval_file = os.path.join(training_args.output_dir, "eval_results_swag.txt")
+        if trainer.is_world_process_zero():
+            with open(output_eval_file, "w") as writer:
+                logger.info("***** Eval results *****")
+                for key, value in sorted(results.items()):
+                    logger.info(f"  {key} = {value}")
+                    writer.write(f"{key} = {value}\n")
+
+    return results
+
+
+def _mp_fn(index):
+    # For xla_spawn (TPUs)
+    main()
+
+
+if __name__ == "__main__":
+    main()

examples/question-answering/README.md

@@ -1,39 +1,43 @@
+<!---
+Copyright 2020 The HuggingFace Team. All rights reserved.
 
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+-->
 
 ## SQuAD
 
-Based on the script [`run_squad.py`](https://github.com/huggingface/transformers/blob/master/examples/question-answering/run_squad.py).
+Based on the script [`run_qa.py`](https://github.com/huggingface/transformers/blob/master/examples/question-answering/run_qa.py).
 
+**Note:** This script only works with models that have a fast tokenizer (backed by the 🤗 Tokenizers library) as it
+uses special features of those tokenizers. You can check if your favorite model has a fast tokenizer in
+[this table](https://huggingface.co/transformers/index.html#bigtable), if it doesn't you can still use the old version
+of the script.
+
+The old version of this script can be found [here](https://github.com/huggingface/transformers/tree/master/examples/legacy/question-answering).
 #### Fine-tuning BERT on SQuAD1.0
 
 This example code fine-tunes BERT on the SQuAD1.0 dataset. It runs in 24 min (with BERT-base) or 68 min (with BERT-large)
-on a single tesla V100 16GB. The data for SQuAD can be downloaded with the following links and should be saved in a
-$SQUAD_DIR directory.
-
-* [train-v1.1.json](https://rajpurkar.github.io/SQuAD-explorer/dataset/train-v1.1.json)
-* [dev-v1.1.json](https://rajpurkar.github.io/SQuAD-explorer/dataset/dev-v1.1.json)
-* [evaluate-v1.1.py](https://github.com/allenai/bi-att-flow/blob/master/squad/evaluate-v1.1.py)
-
-And for SQuAD2.0, you need to download:
-
-- [train-v2.0.json](https://rajpurkar.github.io/SQuAD-explorer/dataset/train-v2.0.json)
-- [dev-v2.0.json](https://rajpurkar.github.io/SQuAD-explorer/dataset/dev-v2.0.json)
-- [evaluate-v2.0.py](https://worksheets.codalab.org/rest/bundles/0x6b567e1cf2e041ec80d7098f031c5c9e/contents/blob/)
+on a single tesla V100 16GB.
 
 ```bash
-export SQUAD_DIR=/path/to/SQUAD
-
-python run_squad.py \
-  --model_type bert \
+python run_qa.py \
   --model_name_or_path bert-base-uncased \
+  --dataset_name squad \
   --do_train \
   --do_eval \
-  --do_lower_case \
-  --train_file $SQUAD_DIR/train-v1.1.json \
-  --predict_file $SQUAD_DIR/dev-v1.1.json \
-  --per_gpu_train_batch_size 12 \
+  --per_device_train_batch_size 12 \
   --learning_rate 3e-5 \
-  --num_train_epochs 2.0 \
+  --num_train_epochs 2 \
   --max_seq_length 384 \
   --doc_stride 128 \
   --output_dir /tmp/debug_squad/
@@ -53,20 +57,17 @@ Here is an example using distributed training on 8 V100 GPUs and Bert Whole Word
 
 ```bash
 python -m torch.distributed.launch --nproc_per_node=8 ./examples/question-answering/run_squad.py \
-    --model_type bert \
     --model_name_or_path bert-large-uncased-whole-word-masking \
+    --dataset_name squad \
     --do_train \
     --do_eval \
-    --do_lower_case \
-    --train_file $SQUAD_DIR/train-v1.1.json \
-    --predict_file $SQUAD_DIR/dev-v1.1.json \
     --learning_rate 3e-5 \
     --num_train_epochs 2 \
     --max_seq_length 384 \
     --doc_stride 128 \
     --output_dir ./examples/models/wwm_uncased_finetuned_squad/ \
-    --per_gpu_eval_batch_size=3   \
-    --per_gpu_train_batch_size=3   \
+    --per_device_eval_batch_size=3   \
+    --per_device_train_batch_size=3   \
 ```
 
 Training with the previously defined hyper-parameters yields the following results:
@@ -79,29 +80,25 @@ exact_match = 86.91
 This fine-tuned model is available as a checkpoint under the reference
 [`bert-large-uncased-whole-word-masking-finetuned-squad`](https://huggingface.co/bert-large-uncased-whole-word-masking-finetuned-squad).
 
-#### Fine-tuning XLNet on SQuAD
+#### Fine-tuning XLNet with beam search on SQuAD
 
-This example code fine-tunes XLNet on both SQuAD1.0 and SQuAD2.0 dataset. See above to download the data for SQuAD .
+This example code fine-tunes XLNet on both SQuAD1.0 and SQuAD2.0 dataset.
 
 ##### Command for SQuAD1.0:
 
 ```bash
-export SQUAD_DIR=/path/to/SQUAD
-
-python run_squad.py \
-    --model_type xlnet \
+python run_qa_beam_search.py \
     --model_name_or_path xlnet-large-cased \
+    --dataset_name squad \
     --do_train \
     --do_eval \
-    --train_file $SQUAD_DIR/train-v1.1.json \
-    --predict_file $SQUAD_DIR/dev-v1.1.json \
     --learning_rate 3e-5 \
     --num_train_epochs 2 \
     --max_seq_length 384 \
     --doc_stride 128 \
     --output_dir ./wwm_cased_finetuned_squad/ \
-    --per_gpu_eval_batch_size=4  \
-    --per_gpu_train_batch_size=4   \
+    --per_device_eval_batch_size=4  \
+    --per_device_train_batch_size=4   \
     --save_steps 5000
 ```
 
@@ -110,21 +107,19 @@ python run_squad.py \
 ```bash
 export SQUAD_DIR=/path/to/SQUAD
 
-python run_squad.py \
-    --model_type xlnet \
+python run_qa_beam_search.py \
     --model_name_or_path xlnet-large-cased \
+    --dataset_name squad_v2 \
     --do_train \
     --do_eval \
     --version_2_with_negative \
-    --train_file $SQUAD_DIR/train-v2.0.json \
-    --predict_file $SQUAD_DIR/dev-v2.0.json \
     --learning_rate 3e-5 \
     --num_train_epochs 4 \
     --max_seq_length 384 \
     --doc_stride 128 \
     --output_dir ./wwm_cased_finetuned_squad/ \
-    --per_gpu_eval_batch_size=2  \
-    --per_gpu_train_batch_size=2   \
+    --per_device_eval_batch_size=2  \
+    --per_device_train_batch_size=2   \
     --save_steps 5000
 ```
 
@@ -162,7 +157,7 @@ Larger batch size may improve the performance while costing more memory.
 #### Fine-tuning BERT on SQuAD1.0 with relative position embeddings
 
 The following examples show how to fine-tune BERT models with different relative position embeddings. The BERT model 
-`bert-base-uncased` was pre-trained with default absolute position embeddings. We provide the following pre-trained 
+`bert-base-uncased` was pretrained with default absolute position embeddings. We provide the following pretrained 
 models which were pre-trained on the same training data (BooksCorpus and English Wikipedia) as in the BERT model 
 training, but with different relative position embeddings. 
 
@@ -178,24 +173,19 @@ in Huang et al. [Improve Transformer Models with Better Relative Position Embedd
 ##### Base models fine-tuning
 
 ```bash
-export SQUAD_DIR=/path/to/SQUAD
-output_dir=relative_squad
 export CUDA_VISIBLE_DEVICES=0,1,2,3,4,5,6,7
 python -m torch.distributed.launch --nproc_per_node=8 ./examples/question-answering/run_squad.py \
-    --model_type bert \
     --model_name_or_path zhiheng-huang/bert-base-uncased-embedding-relative-key-query \
+    --dataset_name squad \
     --do_train \
     --do_eval \
-    --do_lower_case \
-    --train_file $SQUAD_DIR/train-v1.1.json \
-    --predict_file $SQUAD_DIR/dev-v1.1.json \
     --learning_rate 3e-5 \
     --num_train_epochs 2 \
     --max_seq_length 512 \
     --doc_stride 128 \
-    --output_dir ${output_dir} \
-    --per_gpu_eval_batch_size=60 \
-    --per_gpu_train_batch_size=6
+    --output_dir relative_squad \
+    --per_device_eval_batch_size=60 \
+    --per_device_train_batch_size=6
 ```
 Training with the above command leads to the following results. It boosts the BERT default from f1 score of 88.52 to 90.54.
 
@@ -211,22 +201,17 @@ gpu training leads to the f1 score of 90.71.
 ##### Large models fine-tuning
 
 ```bash
-export SQUAD_DIR=/path/to/SQUAD
-output_dir=relative_squad
 export CUDA_VISIBLE_DEVICES=0,1,2,3,4,5,6,7
 python -m torch.distributed.launch --nproc_per_node=8 ./examples/question-answering/run_squad.py \
-    --model_type bert \
     --model_name_or_path zhiheng-huang/bert-large-uncased-whole-word-masking-embedding-relative-key-query \
+    --dataset_name squad \
     --do_train \
     --do_eval \
-    --do_lower_case \
-    --train_file $SQUAD_DIR/train-v1.1.json \
-    --predict_file $SQUAD_DIR/dev-v1.1.json \
     --learning_rate 3e-5 \
     --num_train_epochs 2 \
     --max_seq_length 512 \
     --doc_stride 128 \
-    --output_dir ${output_dir} \
+    --output_dir relative_squad \
     --per_gpu_eval_batch_size=6 \
     --per_gpu_train_batch_size=2 \
     --gradient_accumulation_steps 3
@@ -251,5 +236,4 @@ python run_tf_squad.py \
     --doc_stride 128    
 ```
 
-
 For the moment evaluation is not available in the Tensorflow Trainer only the training.

examples/question-answering/requirements.txt

@@ -0,0 +1 @@
+datasets >= 1.1.3

examples/question-answering/run_qa.py

@@ -0,0 +1,480 @@
+# coding=utf-8
+# Copyright 2020 The HuggingFace Team All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""
+Fine-tuning the library models for question answering.
+"""
+# You can also adapt this script on your own question answering task. Pointers for this are left as comments.
+
+import logging
+import os
+import sys
+from dataclasses import dataclass, field
+from typing import Optional
+
+from datasets import load_dataset, load_metric
+
+import transformers
+from trainer_qa import QuestionAnsweringTrainer
+from transformers import (
+    AutoConfig,
+    AutoModelForQuestionAnswering,
+    AutoTokenizer,
+    DataCollatorWithPadding,
+    EvalPrediction,
+    HfArgumentParser,
+    PreTrainedTokenizerFast,
+    TrainingArguments,
+    default_data_collator,
+    set_seed,
+)
+from transformers.trainer_utils import is_main_process
+from utils_qa import postprocess_qa_predictions
+
+
+logger = logging.getLogger(__name__)
+
+
+@dataclass
+class ModelArguments:
+    """
+    Arguments pertaining to which model/config/tokenizer we are going to fine-tune from.
+    """
+
+    model_name_or_path: str = field(
+        metadata={"help": "Path to pretrained model or model identifier from huggingface.co/models"}
+    )
+    config_name: Optional[str] = field(
+        default=None, metadata={"help": "Pretrained config name or path if not the same as model_name"}
+    )
+    tokenizer_name: Optional[str] = field(
+        default=None, metadata={"help": "Pretrained tokenizer name or path if not the same as model_name"}
+    )
+    cache_dir: Optional[str] = field(
+        default=None,
+        metadata={"help": "Path to directory to store the pretrained models downloaded from huggingface.co"},
+    )
+
+
+@dataclass
+class DataTrainingArguments:
+    """
+    Arguments pertaining to what data we are going to input our model for training and eval.
+    """
+
+    dataset_name: Optional[str] = field(
+        default=None, metadata={"help": "The name of the dataset to use (via the datasets library)."}
+    )
+    dataset_config_name: Optional[str] = field(
+        default=None, metadata={"help": "The configuration name of the dataset to use (via the datasets library)."}
+    )
+    train_file: Optional[str] = field(default=None, metadata={"help": "The input training data file (a text file)."})
+    validation_file: Optional[str] = field(
+        default=None,
+        metadata={"help": "An optional input evaluation data file to evaluate the perplexity on (a text file)."},
+    )
+    overwrite_cache: bool = field(
+        default=False, metadata={"help": "Overwrite the cached training and evaluation sets"}
+    )
+    preprocessing_num_workers: Optional[int] = field(
+        default=None,
+        metadata={"help": "The number of processes to use for the preprocessing."},
+    )
+    max_seq_length: int = field(
+        default=384,
+        metadata={
+            "help": "The maximum total input sequence length after tokenization. Sequences longer "
+            "than this will be truncated, sequences shorter will be padded."
+        },
+    )
+    pad_to_max_length: bool = field(
+        default=True,
+        metadata={
+            "help": "Whether to pad all samples to `max_seq_length`. "
+            "If False, will pad the samples dynamically when batching to the maximum length in the batch (which can "
+            "be faster on GPU but will be slower on TPU)."
+        },
+    )
+    version_2_with_negative: bool = field(
+        default=False, metadata={"help": "If true, some of the examples do not have an answer."}
+    )
+    null_score_diff_threshold: float = field(
+        default=0.0,
+        metadata={
+            "help": "The threshold used to select the null answer: if the best answer has a score that is less than "
+            "the score of the null answer minus this threshold, the null answer is selected for this example. "
+            "Only useful when `version_2_with_negative=True`."
+        },
+    )
+    doc_stride: int = field(
+        default=128,
+        metadata={"help": "When splitting up a long document into chunks, how much stride to take between chunks."},
+    )
+    n_best_size: int = field(
+        default=20,
+        metadata={"help": "The total number of n-best predictions to generate when looking for an answer."},
+    )
+    max_answer_length: int = field(
+        default=30,
+        metadata={
+            "help": "The maximum length of an answer that can be generated. This is needed because the start "
+            "and end predictions are not conditioned on one another."
+        },
+    )
+
+    def __post_init__(self):
+        if self.dataset_name is None and self.train_file is None and self.validation_file is None:
+            raise ValueError("Need either a dataset name or a training/validation file.")
+        else:
+            if self.train_file is not None:
+                extension = self.train_file.split(".")[-1]
+                assert extension in ["csv", "json"], "`train_file` should be a csv or a json file."
+            if self.validation_file is not None:
+                extension = self.validation_file.split(".")[-1]
+                assert extension in ["csv", "json"], "`validation_file` should be a csv or a json file."
+
+
+def main():
+    # See all possible arguments in src/transformers/training_args.py
+    # or by passing the --help flag to this script.
+    # We now keep distinct sets of args, for a cleaner separation of concerns.
+
+    parser = HfArgumentParser((ModelArguments, DataTrainingArguments, TrainingArguments))
+    if len(sys.argv) == 2 and sys.argv[1].endswith(".json"):
+        # If we pass only one argument to the script and it's the path to a json file,
+        # let's parse it to get our arguments.
+        model_args, data_args, training_args = parser.parse_json_file(json_file=os.path.abspath(sys.argv[1]))
+    else:
+        model_args, data_args, training_args = parser.parse_args_into_dataclasses()
+
+    if (
+        os.path.exists(training_args.output_dir)
+        and os.listdir(training_args.output_dir)
+        and training_args.do_train
+        and not training_args.overwrite_output_dir
+    ):
+        raise ValueError(
+            f"Output directory ({training_args.output_dir}) already exists and is not empty."
+            "Use --overwrite_output_dir to overcome."
+        )
+
+    # Setup logging
+    logging.basicConfig(
+        format="%(asctime)s - %(levelname)s - %(name)s -   %(message)s",
+        datefmt="%m/%d/%Y %H:%M:%S",
+    )
+    logger.setLevel(logging.INFO if is_main_process(training_args.local_rank) else logging.WARN)
+
+    # Log on each process the small summary:
+    logger.warning(
+        f"Process rank: {training_args.local_rank}, device: {training_args.device}, n_gpu: {training_args.n_gpu}"
+        + f"distributed training: {bool(training_args.local_rank != -1)}, 16-bits training: {training_args.fp16}"
+    )
+    # Set the verbosity to info of the Transformers logger (on main process only):
+    if is_main_process(training_args.local_rank):
+        transformers.utils.logging.set_verbosity_info()
+    logger.info("Training/evaluation parameters %s", training_args)
+
+    # Set seed before initializing model.
+    set_seed(training_args.seed)
+
+    # Get the datasets: you can either provide your own CSV/JSON/TXT training and evaluation files (see below)
+    # or just provide the name of one of the public datasets available on the hub at https://huggingface.co/datasets/
+    # (the dataset will be downloaded automatically from the datasets Hub).
+    #
+    # For CSV/JSON files, this script will use the column called 'text' or the first column if no column called
+    # 'text' is found. You can easily tweak this behavior (see below).
+    #
+    # In distributed training, the load_dataset function guarantee that only one local process can concurrently
+    # download the dataset.
+    if data_args.dataset_name is not None:
+        # Downloading and loading a dataset from the hub.
+        datasets = load_dataset(data_args.dataset_name, data_args.dataset_config_name)
+    else:
+        data_files = {}
+        if data_args.train_file is not None:
+            data_files["train"] = data_args.train_file
+        if data_args.validation_file is not None:
+            data_files["validation"] = data_args.validation_file
+        extension = data_args.train_file.split(".")[-1]
+        datasets = load_dataset(extension, data_files=data_files, field="data")
+    # See more about loading any type of standard or custom dataset (from files, python dict, pandas DataFrame, etc) at
+    # https://huggingface.co/docs/datasets/loading_datasets.html.
+
+    # Load pretrained model and tokenizer
+    #
+    # Distributed training:
+    # The .from_pretrained methods guarantee that only one local process can concurrently
+    # download model & vocab.
+    config = AutoConfig.from_pretrained(
+        model_args.config_name if model_args.config_name else model_args.model_name_or_path,
+        cache_dir=model_args.cache_dir,
+    )
+    tokenizer = AutoTokenizer.from_pretrained(
+        model_args.tokenizer_name if model_args.tokenizer_name else model_args.model_name_or_path,
+        cache_dir=model_args.cache_dir,
+        use_fast=True,
+    )
+    model = AutoModelForQuestionAnswering.from_pretrained(
+        model_args.model_name_or_path,
+        from_tf=bool(".ckpt" in model_args.model_name_or_path),
+        config=config,
+        cache_dir=model_args.cache_dir,
+    )
+
+    # Tokenizer check: this script requires a fast tokenizer.
+    if not isinstance(tokenizer, PreTrainedTokenizerFast):
+        raise ValueError(
+            "This example script only works for models that have a fast tokenizer. Checkout the big table of models "
+            "at https://huggingface.co/transformers/index.html#bigtable to find the model types that meet this "
+            "requirement"
+        )
+
+    # Preprocessing the datasets.
+    # Preprocessing is slighlty different for training and evaluation.
+    if training_args.do_train:
+        column_names = datasets["train"].column_names
+    else:
+        column_names = datasets["validation"].column_names
+    question_column_name = "question" if "question" in column_names else column_names[0]
+    context_column_name = "context" if "context" in column_names else column_names[1]
+    answer_column_name = "answers" if "answers" in column_names else column_names[2]
+
+    # Padding side determines if we do (question|context) or (context|question).
+    pad_on_right = tokenizer.padding_side == "right"
+
+    # Training preprocessing
+    def prepare_train_features(examples):
+        # Tokenize our examples with truncation and maybe padding, but keep the overflows using a stride. This results
+        # in one example possible giving several features when a context is long, each of those features having a
+        # context that overlaps a bit the context of the previous feature.
+        tokenized_examples = tokenizer(
+            examples[question_column_name if pad_on_right else context_column_name],
+            examples[context_column_name if pad_on_right else question_column_name],
+            truncation="only_second" if pad_on_right else "only_first",
+            max_length=data_args.max_seq_length,
+            stride=data_args.doc_stride,
+            return_overflowing_tokens=True,
+            return_offsets_mapping=True,
+            padding="max_length" if data_args.pad_to_max_length else False,
+        )
+
+        # Since one example might give us several features if it has a long context, we need a map from a feature to
+        # its corresponding example. This key gives us just that.
+        sample_mapping = tokenized_examples.pop("overflow_to_sample_mapping")
+        # The offset mappings will give us a map from token to character position in the original context. This will
+        # help us compute the start_positions and end_positions.
+        offset_mapping = tokenized_examples.pop("offset_mapping")
+
+        # Let's label those examples!
+        tokenized_examples["start_positions"] = []
+        tokenized_examples["end_positions"] = []
+
+        for i, offsets in enumerate(offset_mapping):
+            # We will label impossible answers with the index of the CLS token.
+            input_ids = tokenized_examples["input_ids"][i]
+            cls_index = input_ids.index(tokenizer.cls_token_id)
+
+            # Grab the sequence corresponding to that example (to know what is the context and what is the question).
+            sequence_ids = tokenized_examples.sequence_ids(i)
+
+            # One example can give several spans, this is the index of the example containing this span of text.
+            sample_index = sample_mapping[i]
+            answers = examples[answer_column_name][sample_index]
+            # If no answers are given, set the cls_index as answer.
+            if len(answers["answer_start"]) == 0:
+                tokenized_examples["start_positions"].append(cls_index)
+                tokenized_examples["end_positions"].append(cls_index)
+            else:
+                # Start/end character index of the answer in the text.
+                start_char = answers["answer_start"][0]
+                end_char = start_char + len(answers["text"][0])
+
+                # Start token index of the current span in the text.
+                token_start_index = 0
+                while sequence_ids[token_start_index] != (1 if pad_on_right else 0):
+                    token_start_index += 1
+
+                # End token index of the current span in the text.
+                token_end_index = len(input_ids) - 1
+                while sequence_ids[token_end_index] != (1 if pad_on_right else 0):
+                    token_end_index -= 1
+
+                # Detect if the answer is out of the span (in which case this feature is labeled with the CLS index).
+                if not (offsets[token_start_index][0] <= start_char and offsets[token_end_index][1] >= end_char):
+                    tokenized_examples["start_positions"].append(cls_index)
+                    tokenized_examples["end_positions"].append(cls_index)
+                else:
+                    # Otherwise move the token_start_index and token_end_index to the two ends of the answer.
+                    # Note: we could go after the last offset if the answer is the last word (edge case).
+                    while token_start_index < len(offsets) and offsets[token_start_index][0] <= start_char:
+                        token_start_index += 1
+                    tokenized_examples["start_positions"].append(token_start_index - 1)
+                    while offsets[token_end_index][1] >= end_char:
+                        token_end_index -= 1
+                    tokenized_examples["end_positions"].append(token_end_index + 1)
+
+        return tokenized_examples
+
+    if training_args.do_train:
+        train_dataset = datasets["train"].map(
+            prepare_train_features,
+            batched=True,
+            num_proc=data_args.preprocessing_num_workers,
+            remove_columns=column_names,
+            load_from_cache_file=not data_args.overwrite_cache,
+        )
+
+    # Validation preprocessing
+    def prepare_validation_features(examples):
+        # Tokenize our examples with truncation and maybe padding, but keep the overflows using a stride. This results
+        # in one example possible giving several features when a context is long, each of those features having a
+        # context that overlaps a bit the context of the previous feature.
+        tokenized_examples = tokenizer(
+            examples[question_column_name if pad_on_right else context_column_name],
+            examples[context_column_name if pad_on_right else question_column_name],
+            truncation="only_second" if pad_on_right else "only_first",
+            max_length=data_args.max_seq_length,
+            stride=data_args.doc_stride,
+            return_overflowing_tokens=True,
+            return_offsets_mapping=True,
+            padding="max_length" if data_args.pad_to_max_length else False,
+        )
+
+        # Since one example might give us several features if it has a long context, we need a map from a feature to
+        # its corresponding example. This key gives us just that.
+        sample_mapping = tokenized_examples.pop("overflow_to_sample_mapping")
+
+        # For evaluation, we will need to convert our predictions to substrings of the context, so we keep the
+        # corresponding example_id and we will store the offset mappings.
+        tokenized_examples["example_id"] = []
+
+        for i in range(len(tokenized_examples["input_ids"])):
+            # Grab the sequence corresponding to that example (to know what is the context and what is the question).
+            sequence_ids = tokenized_examples.sequence_ids(i)
+            context_index = 1 if pad_on_right else 0
+
+            # One example can give several spans, this is the index of the example containing this span of text.
+            sample_index = sample_mapping[i]
+            tokenized_examples["example_id"].append(examples["id"][sample_index])
+
+            # Set to None the offset_mapping that are not part of the context so it's easy to determine if a token
+            # position is part of the context or not.
+            tokenized_examples["offset_mapping"][i] = [
+                (o if sequence_ids[k] == context_index else None)
+                for k, o in enumerate(tokenized_examples["offset_mapping"][i])
+            ]
+
+        return tokenized_examples
+
+    if training_args.do_eval:
+        validation_dataset = datasets["validation"].map(
+            prepare_validation_features,
+            batched=True,
+            num_proc=data_args.preprocessing_num_workers,
+            remove_columns=column_names,
+            load_from_cache_file=not data_args.overwrite_cache,
+        )
+
+    # Data collator
+    # We have already padded to max length if the corresponding flag is True, otherwise we need to pad in the data
+    # collator.
+    data_collator = default_data_collator if data_args.pad_to_max_length else DataCollatorWithPadding(tokenizer)
+
+    # Post-processing:
+    def post_processing_function(examples, features, predictions):
+        # Post-processing: we match the start logits and end logits to answers in the original context.
+        predictions = postprocess_qa_predictions(
+            examples=examples,
+            features=features,
+            predictions=predictions,
+            version_2_with_negative=data_args.version_2_with_negative,
+            n_best_size=data_args.n_best_size,
+            max_answer_length=data_args.max_answer_length,
+            null_score_diff_threshold=data_args.null_score_diff_threshold,
+            output_dir=training_args.output_dir,
+            is_world_process_zero=trainer.is_world_process_zero(),
+        )
+        # Format the result to the format the metric expects.
+        if data_args.version_2_with_negative:
+            formatted_predictions = [
+                {"id": k, "prediction_text": v, "no_answer_probability": 0.0} for k, v in predictions.items()
+            ]
+        else:
+            formatted_predictions = [{"id": k, "prediction_text": v} for k, v in predictions.items()]
+        references = [{"id": ex["id"], "answers": ex[answer_column_name]} for ex in datasets["validation"]]
+        return EvalPrediction(predictions=formatted_predictions, label_ids=references)
+
+    # TODO: Once the fix lands in a Datasets release, remove the _local here and the squad_v2_local folder.
+    current_dir = os.path.sep.join(os.path.join(__file__).split(os.path.sep)[:-1])
+    metric = load_metric(os.path.join(current_dir, "squad_v2_local") if data_args.version_2_with_negative else "squad")
+
+    def compute_metrics(p: EvalPrediction):
+        return metric.compute(predictions=p.predictions, references=p.label_ids)
+
+    # Initialize our Trainer
+    trainer = QuestionAnsweringTrainer(
+        model=model,
+        args=training_args,
+        train_dataset=train_dataset if training_args.do_train else None,
+        eval_dataset=validation_dataset if training_args.do_eval else None,
+        eval_examples=datasets["validation"] if training_args.do_eval else None,
+        tokenizer=tokenizer,
+        data_collator=data_collator,
+        post_process_function=post_processing_function,
+        compute_metrics=compute_metrics,
+    )
+
+    # Training
+    if training_args.do_train:
+        train_result = trainer.train(
+            model_path=model_args.model_name_or_path if os.path.isdir(model_args.model_name_or_path) else None
+        )
+        trainer.save_model()  # Saves the tokenizer too for easy upload
+
+        output_train_file = os.path.join(training_args.output_dir, "train_results.txt")
+        if trainer.is_world_process_zero():
+            with open(output_train_file, "w") as writer:
+                logger.info("***** Train results *****")
+                for key, value in sorted(train_result.metrics.items()):
+                    logger.info(f"  {key} = {value}")
+                    writer.write(f"{key} = {value}\n")
+
+            # Need to save the state, since Trainer.save_model saves only the tokenizer with the model
+            trainer.state.save_to_json(os.path.join(training_args.output_dir, "trainer_state.json"))
+
+    # Evaluation
+    results = {}
+    if training_args.do_eval:
+        logger.info("*** Evaluate ***")
+        results = trainer.evaluate()
+
+        output_eval_file = os.path.join(training_args.output_dir, "eval_results.txt")
+        if trainer.is_world_process_zero():
+            with open(output_eval_file, "w") as writer:
+                logger.info("***** Eval results *****")
+                for key, value in sorted(results.items()):
+                    logger.info(f"  {key} = {value}")
+                    writer.write(f"{key} = {value}\n")
+
+    return results
+
+
+def _mp_fn(index):
+    # For xla_spawn (TPUs)
+    main()
+
+
+if __name__ == "__main__":
+    main()

examples/question-answering/run_qa_beam_search.py

@@ -0,0 +1,523 @@
+# coding=utf-8
+# Copyright 2020 The HuggingFace Team All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""
+Fine-tuning XLNet for question answering with beam search.
+"""
+# You can also adapt this script on your own question answering task. Pointers for this are left as comments.
+
+import logging
+import os
+import sys
+from dataclasses import dataclass, field
+from typing import Optional
+
+from datasets import load_dataset, load_metric
+
+import transformers
+from trainer_qa import QuestionAnsweringTrainer
+from transformers import (
+    DataCollatorWithPadding,
+    EvalPrediction,
+    HfArgumentParser,
+    TrainingArguments,
+    XLNetConfig,
+    XLNetForQuestionAnswering,
+    XLNetTokenizerFast,
+    default_data_collator,
+    set_seed,
+)
+from transformers.trainer_utils import is_main_process
+from utils_qa import postprocess_qa_predictions_with_beam_search
+
+
+logger = logging.getLogger(__name__)
+
+
+@dataclass
+class ModelArguments:
+    """
+    Arguments pertaining to which model/config/tokenizer we are going to fine-tune from.
+    """
+
+    model_name_or_path: str = field(
+        metadata={"help": "Path to pretrained model or model identifier from huggingface.co/models"}
+    )
+    config_name: Optional[str] = field(
+        default=None, metadata={"help": "Pretrained config name or path if not the same as model_name"}
+    )
+    tokenizer_name: Optional[str] = field(
+        default=None, metadata={"help": "Pretrained tokenizer name or path if not the same as model_name"}
+    )
+    cache_dir: Optional[str] = field(
+        default=None,
+        metadata={"help": "Where do you want to store the pretrained models downloaded from huggingface.co"},
+    )
+    use_fast_tokenizer: bool = field(
+        default=True,
+        metadata={"help": "Whether to use one of the fast tokenizer (backed by the tokenizers library) or not."},
+    )
+
+
+@dataclass
+class DataTrainingArguments:
+    """
+    Arguments pertaining to what data we are going to input our model for training and eval.
+    """
+
+    dataset_name: Optional[str] = field(
+        default=None, metadata={"help": "The name of the dataset to use (via the datasets library)."}
+    )
+    dataset_config_name: Optional[str] = field(
+        default=None, metadata={"help": "The configuration name of the dataset to use (via the datasets library)."}
+    )
+    train_file: Optional[str] = field(default=None, metadata={"help": "The input training data file (a text file)."})
+    validation_file: Optional[str] = field(
+        default=None,
+        metadata={"help": "An optional input evaluation data file to evaluate the perplexity on (a text file)."},
+    )
+    overwrite_cache: bool = field(
+        default=False, metadata={"help": "Overwrite the cached training and evaluation sets"}
+    )
+    preprocessing_num_workers: Optional[int] = field(
+        default=None,
+        metadata={"help": "The number of processes to use for the preprocessing."},
+    )
+    max_seq_length: int = field(
+        default=384,
+        metadata={
+            "help": "The maximum total input sequence length after tokenization. Sequences longer "
+            "than this will be truncated, sequences shorter will be padded."
+        },
+    )
+    pad_to_max_length: bool = field(
+        default=True,
+        metadata={
+            "help": "Whether to pad all samples to `max_seq_length`. "
+            "If False, will pad the samples dynamically when batching to the maximum length in the batch (which can "
+            "be faster on GPU but will be slower on TPU)."
+        },
+    )
+    version_2_with_negative: bool = field(
+        default=False, metadata={"help": "If true, some of the examples do not have an answer."}
+    )
+    null_score_diff_threshold: float = field(
+        default=0.0,
+        metadata={
+            "help": "The threshold used to select the null answer: if the best answer has a score that is less than "
+            "the score of the null answer minus this threshold, the null answer is selected for this example. "
+            "Only useful when `version_2_with_negative=True`."
+        },
+    )
+    doc_stride: int = field(
+        default=128,
+        metadata={"help": "When splitting up a long document into chunks, how much stride to take between chunks."},
+    )
+    n_best_size: int = field(
+        default=20,
+        metadata={"help": "The total number of n-best predictions to generate when looking for an answer."},
+    )
+    max_answer_length: int = field(
+        default=30,
+        metadata={
+            "help": "The maximum length of an answer that can be generated. This is needed because the start "
+            "and end predictions are not conditioned on one another."
+        },
+    )
+
+    def __post_init__(self):
+        if self.dataset_name is None and self.train_file is None and self.validation_file is None:
+            raise ValueError("Need either a dataset name or a training/validation file.")
+        else:
+            if self.train_file is not None:
+                extension = self.train_file.split(".")[-1]
+                assert extension in ["csv", "json"], "`train_file` should be a csv or a json file."
+            if self.validation_file is not None:
+                extension = self.validation_file.split(".")[-1]
+                assert extension in ["csv", "json"], "`validation_file` should be a csv or a json file."
+
+
+def main():
+    # See all possible arguments in src/transformers/training_args.py
+    # or by passing the --help flag to this script.
+    # We now keep distinct sets of args, for a cleaner separation of concerns.
+
+    parser = HfArgumentParser((ModelArguments, DataTrainingArguments, TrainingArguments))
+    if len(sys.argv) == 2 and sys.argv[1].endswith(".json"):
+        # If we pass only one argument to the script and it's the path to a json file,
+        # let's parse it to get our arguments.
+        model_args, data_args, training_args = parser.parse_json_file(json_file=os.path.abspath(sys.argv[1]))
+    else:
+        model_args, data_args, training_args = parser.parse_args_into_dataclasses()
+
+    if (
+        os.path.exists(training_args.output_dir)
+        and os.listdir(training_args.output_dir)
+        and training_args.do_train
+        and not training_args.overwrite_output_dir
+    ):
+        raise ValueError(
+            f"Output directory ({training_args.output_dir}) already exists and is not empty."
+            "Use --overwrite_output_dir to overcome."
+        )
+
+    # Setup logging
+    logging.basicConfig(
+        format="%(asctime)s - %(levelname)s - %(name)s -   %(message)s",
+        datefmt="%m/%d/%Y %H:%M:%S",
+    )
+    logger.setLevel(logging.INFO if is_main_process(training_args.local_rank) else logging.WARN)
+
+    # Log on each process the small summary:
+    logger.warning(
+        f"Process rank: {training_args.local_rank}, device: {training_args.device}, n_gpu: {training_args.n_gpu}"
+        + f"distributed training: {bool(training_args.local_rank != -1)}, 16-bits training: {training_args.fp16}"
+    )
+    # Set the verbosity to info of the Transformers logger (on main process only):
+    if is_main_process(training_args.local_rank):
+        transformers.utils.logging.set_verbosity_info()
+    logger.info("Training/evaluation parameters %s", training_args)
+
+    # Set seed before initializing model.
+    set_seed(training_args.seed)
+
+    # Get the datasets: you can either provide your own CSV/JSON/TXT training and evaluation files (see below)
+    # or just provide the name of one of the public datasets available on the hub at https://huggingface.co/datasets/
+    # (the dataset will be downloaded automatically from the datasets Hub).
+    #
+    # For CSV/JSON files, this script will use the column called 'text' or the first column if no column called
+    # 'text' is found. You can easily tweak this behavior (see below).
+    #
+    # In distributed training, the load_dataset function guarantee that only one local process can concurrently
+    # download the dataset.
+    if data_args.dataset_name is not None:
+        # Downloading and loading a dataset from the hub.
+        datasets = load_dataset(data_args.dataset_name, data_args.dataset_config_name)
+    else:
+        data_files = {}
+        if data_args.train_file is not None:
+            data_files["train"] = data_args.train_file
+        if data_args.validation_file is not None:
+            data_files["validation"] = data_args.validation_file
+        extension = data_args.train_file.split(".")[-1]
+        datasets = load_dataset(extension, data_files=data_files, field="data")
+    # See more about loading any type of standard or custom dataset (from files, python dict, pandas DataFrame, etc) at
+    # https://huggingface.co/docs/datasets/loading_datasets.html.
+
+    # Load pretrained model and tokenizer
+    #
+    # Distributed training:
+    # The .from_pretrained methods guarantee that only one local process can concurrently
+    # download model & vocab.
+    config = XLNetConfig.from_pretrained(
+        model_args.config_name if model_args.config_name else model_args.model_name_or_path,
+        cache_dir=model_args.cache_dir,
+    )
+    tokenizer = XLNetTokenizerFast.from_pretrained(
+        model_args.tokenizer_name if model_args.tokenizer_name else model_args.model_name_or_path,
+        cache_dir=model_args.cache_dir,
+    )
+    model = XLNetForQuestionAnswering.from_pretrained(
+        model_args.model_name_or_path,
+        from_tf=bool(".ckpt" in model_args.model_name_or_path),
+        config=config,
+        cache_dir=model_args.cache_dir,
+    )
+
+    # Preprocessing the datasets.
+    # Preprocessing is slighlty different for training and evaluation.
+    if training_args.do_train:
+        column_names = datasets["train"].column_names
+    else:
+        column_names = datasets["validation"].column_names
+    question_column_name = "question" if "question" in column_names else column_names[0]
+    context_column_name = "context" if "context" in column_names else column_names[1]
+    answer_column_name = "answers" if "answers" in column_names else column_names[2]
+
+    # Padding side determines if we do (question|context) or (context|question).
+    pad_on_right = tokenizer.padding_side == "right"
+
+    # Training preprocessing
+    def prepare_train_features(examples):
+        # Tokenize our examples with truncation and maybe padding, but keep the overflows using a stride. This results
+        # in one example possible giving several features when a context is long, each of those features having a
+        # context that overlaps a bit the context of the previous feature.
+        tokenized_examples = tokenizer(
+            examples[question_column_name if pad_on_right else context_column_name],
+            examples[context_column_name if pad_on_right else question_column_name],
+            truncation="only_second" if pad_on_right else "only_first",
+            max_length=data_args.max_seq_length,
+            stride=data_args.doc_stride,
+            return_overflowing_tokens=True,
+            return_offsets_mapping=True,
+            return_special_tokens_mask=True,
+            return_token_type_ids=True,
+            padding="max_length",
+        )
+
+        # Since one example might give us several features if it has a long context, we need a map from a feature to
+        # its corresponding example. This key gives us just that.
+        sample_mapping = tokenized_examples.pop("overflow_to_sample_mapping")
+        # The offset mappings will give us a map from token to character position in the original context. This will
+        # help us compute the start_positions and end_positions.
+        offset_mapping = tokenized_examples.pop("offset_mapping")
+        # The special tokens will help us build the p_mask (which indicates the tokens that can't be in answers).
+        special_tokens = tokenized_examples.pop("special_tokens_mask")
+
+        # Let's label those examples!
+        tokenized_examples["start_positions"] = []
+        tokenized_examples["end_positions"] = []
+        tokenized_examples["is_impossible"] = []
+        tokenized_examples["cls_index"] = []
+        tokenized_examples["p_mask"] = []
+
+        for i, offsets in enumerate(offset_mapping):
+            # We will label impossible answers with the index of the CLS token.
+            input_ids = tokenized_examples["input_ids"][i]
+            cls_index = input_ids.index(tokenizer.cls_token_id)
+            tokenized_examples["cls_index"].append(cls_index)
+
+            # Grab the sequence corresponding to that example (to know what is the context and what is the question).
+            sequence_ids = tokenized_examples["token_type_ids"][i]
+            for k, s in enumerate(special_tokens[i]):
+                if s:
+                    sequence_ids[k] = 3
+            context_idx = 1 if pad_on_right else 0
+
+            # Build the p_mask: non special tokens and context gets 0.0, the others get 1.0.
+            # The cls token gets 1.0 too (for predictions of empty answers).
+            tokenized_examples["p_mask"].append(
+                [
+                    0.0 if (not special_tokens[i][k] and s == context_idx) or k == cls_index else 1.0
+                    for k, s in enumerate(sequence_ids)
+                ]
+            )
+
+            # One example can give several spans, this is the index of the example containing this span of text.
+            sample_index = sample_mapping[i]
+            answers = examples[answer_column_name][sample_index]
+            # If no answers are given, set the cls_index as answer.
+            if len(answers["answer_start"]) == 0:
+                tokenized_examples["start_positions"].append(cls_index)
+                tokenized_examples["end_positions"].append(cls_index)
+                tokenized_examples["is_impossible"].append(1.0)
+            else:
+                # Start/end character index of the answer in the text.
+                start_char = answers["answer_start"][0]
+                end_char = start_char + len(answers["text"][0])
+
+                # Start token index of the current span in the text.
+                token_start_index = 0
+                while sequence_ids[token_start_index] != context_idx:
+                    token_start_index += 1
+
+                # End token index of the current span in the text.
+                token_end_index = len(input_ids) - 1
+                while sequence_ids[token_end_index] != context_idx:
+                    token_end_index -= 1
+                # Detect if the answer is out of the span (in which case this feature is labeled with the CLS index).
+                if not (offsets[token_start_index][0] <= start_char and offsets[token_end_index][1] >= end_char):
+                    tokenized_examples["start_positions"].append(cls_index)
+                    tokenized_examples["end_positions"].append(cls_index)
+                    tokenized_examples["is_impossible"].append(1.0)
+                else:
+                    # Otherwise move the token_start_index and token_end_index to the two ends of the answer.
+                    # Note: we could go after the last offset if the answer is the last word (edge case).
+                    while token_start_index < len(offsets) and offsets[token_start_index][0] <= start_char:
+                        token_start_index += 1
+                    tokenized_examples["start_positions"].append(token_start_index - 1)
+                    while offsets[token_end_index][1] >= end_char:
+                        token_end_index -= 1
+                    tokenized_examples["end_positions"].append(token_end_index + 1)
+                    tokenized_examples["is_impossible"].append(0.0)
+
+        return tokenized_examples
+
+    if training_args.do_train:
+        train_dataset = datasets["train"].map(
+            prepare_train_features,
+            batched=True,
+            num_proc=data_args.preprocessing_num_workers,
+            remove_columns=column_names,
+            load_from_cache_file=not data_args.overwrite_cache,
+        )
+
+    # Validation preprocessing
+    def prepare_validation_features(examples):
+        # Tokenize our examples with truncation and maybe padding, but keep the overflows using a stride. This results
+        # in one example possible giving several features when a context is long, each of those features having a
+        # context that overlaps a bit the context of the previous feature.
+        tokenized_examples = tokenizer(
+            examples[question_column_name if pad_on_right else context_column_name],
+            examples[context_column_name if pad_on_right else question_column_name],
+            truncation="only_second" if pad_on_right else "only_first",
+            max_length=data_args.max_seq_length,
+            stride=data_args.doc_stride,
+            return_overflowing_tokens=True,
+            return_offsets_mapping=True,
+            return_special_tokens_mask=True,
+            return_token_type_ids=True,
+            padding="max_length",
+        )
+
+        # Since one example might give us several features if it has a long context, we need a map from a feature to
+        # its corresponding example. This key gives us just that.
+        sample_mapping = tokenized_examples.pop("overflow_to_sample_mapping")
+
+        # The special tokens will help us build the p_mask (which indicates the tokens that can't be in answers).
+        special_tokens = tokenized_examples.pop("special_tokens_mask")
+
+        # For evaluation, we will need to convert our predictions to substrings of the context, so we keep the
+        # corresponding example_id and we will store the offset mappings.
+        tokenized_examples["example_id"] = []
+
+        # We still provide the index of the CLS token and the p_mask to the model, but not the is_impossible label.
+        tokenized_examples["cls_index"] = []
+        tokenized_examples["p_mask"] = []
+
+        for i, input_ids in enumerate(tokenized_examples["input_ids"]):
+            # Find the CLS token in the input ids.
+            cls_index = input_ids.index(tokenizer.cls_token_id)
+            tokenized_examples["cls_index"].append(cls_index)
+
+            # Grab the sequence corresponding to that example (to know what is the context and what is the question).
+            sequence_ids = tokenized_examples["token_type_ids"][i]
+            for k, s in enumerate(special_tokens[i]):
+                if s:
+                    sequence_ids[k] = 3
+            context_idx = 1 if pad_on_right else 0
+
+            # Build the p_mask: non special tokens and context gets 0.0, the others 1.0.
+            tokenized_examples["p_mask"].append(
+                [
+                    0.0 if (not special_tokens[i][k] and s == context_idx) or k == cls_index else 1.0
+                    for k, s in enumerate(sequence_ids)
+                ]
+            )
+
+            # One example can give several spans, this is the index of the example containing this span of text.
+            sample_index = sample_mapping[i]
+            tokenized_examples["example_id"].append(examples["id"][sample_index])
+
+            # Set to None the offset_mapping that are not part of the context so it's easy to determine if a token
+            # position is part of the context or not.
+            tokenized_examples["offset_mapping"][i] = [
+                (o if sequence_ids[k] == context_idx else None)
+                for k, o in enumerate(tokenized_examples["offset_mapping"][i])
+            ]
+
+        return tokenized_examples
+
+    if training_args.do_eval:
+        validation_dataset = datasets["validation"].map(
+            prepare_validation_features,
+            batched=True,
+            num_proc=data_args.preprocessing_num_workers,
+            remove_columns=column_names,
+            load_from_cache_file=not data_args.overwrite_cache,
+        )
+
+    # Data collator
+    # We have already padded to max length if the corresponding flag is True, otherwise we need to pad in the data
+    # collator.
+    data_collator = default_data_collator if data_args.pad_to_max_length else DataCollatorWithPadding(tokenizer)
+
+    # Post-processing:
+    def post_processing_function(examples, features, predictions):
+        # Post-processing: we match the start logits and end logits to answers in the original context.
+        predictions, scores_diff_json = postprocess_qa_predictions_with_beam_search(
+            examples=examples,
+            features=features,
+            predictions=predictions,
+            version_2_with_negative=data_args.version_2_with_negative,
+            n_best_size=data_args.n_best_size,
+            max_answer_length=data_args.max_answer_length,
+            start_n_top=model.config.start_n_top,
+            end_n_top=model.config.end_n_top,
+            output_dir=training_args.output_dir,
+            is_world_process_zero=trainer.is_world_process_zero(),
+        )
+        # Format the result to the format the metric expects.
+        if data_args.version_2_with_negative:
+            formatted_predictions = [
+                {"id": k, "prediction_text": v, "no_answer_probability": scores_diff_json[k]}
+                for k, v in predictions.items()
+            ]
+        else:
+            formatted_predictions = [{"id": k, "prediction_text": v} for k, v in predictions.items()]
+        references = [{"id": ex["id"], "answers": ex[answer_column_name]} for ex in datasets["validation"]]
+        return EvalPrediction(predictions=formatted_predictions, label_ids=references)
+
+    # TODO: Once the fix lands in a Datasets release, remove the _local here and the squad_v2_local folder.
+    current_dir = os.path.sep.join(os.path.join(__file__).split(os.path.sep)[:-1])
+    metric = load_metric(os.path.join(current_dir, "squad_v2_local") if data_args.version_2_with_negative else "squad")
+
+    def compute_metrics(p: EvalPrediction):
+        return metric.compute(predictions=p.predictions, references=p.label_ids)
+
+    # Initialize our Trainer
+    trainer = QuestionAnsweringTrainer(
+        model=model,
+        args=training_args,
+        train_dataset=train_dataset if training_args.do_train else None,
+        eval_dataset=validation_dataset if training_args.do_eval else None,
+        eval_examples=datasets["validation"] if training_args.do_eval else None,
+        tokenizer=tokenizer,
+        data_collator=data_collator,
+        post_process_function=post_processing_function,
+        compute_metrics=compute_metrics,
+    )
+
+    # Training
+    if training_args.do_train:
+        train_result = trainer.train(
+            model_path=model_args.model_name_or_path if os.path.isdir(model_args.model_name_or_path) else None
+        )
+        trainer.save_model()  # Saves the tokenizer too for easy upload
+
+        output_train_file = os.path.join(training_args.output_dir, "train_results.txt")
+        if trainer.is_world_process_zero():
+            with open(output_train_file, "w") as writer:
+                logger.info("***** Train results *****")
+                for key, value in sorted(train_result.metrics.items()):
+                    logger.info(f"  {key} = {value}")
+                    writer.write(f"{key} = {value}\n")
+
+            # Need to save the state, since Trainer.save_model saves only the tokenizer with the model
+            trainer.state.save_to_json(os.path.join(training_args.output_dir, "trainer_state.json"))
+
+    # Evaluation
+    results = {}
+    if training_args.do_eval:
+        logger.info("*** Evaluate ***")
+        results = trainer.evaluate()
+
+        output_eval_file = os.path.join(training_args.output_dir, "eval_results.txt")
+        if trainer.is_world_process_zero():
+            with open(output_eval_file, "w") as writer:
+                logger.info("***** Eval results *****")
+                for key, value in sorted(results.items()):
+                    logger.info(f"  {key} = {value}")
+                    writer.write(f"{key} = {value}\n")
+
+    return results
+
+
+def _mp_fn(index):
+    # For xla_spawn (TPUs)
+    main()
+
+
+if __name__ == "__main__":
+    main()

examples/question-answering/squad_v2_local/evaluate.py

@@ -0,0 +1,322 @@
+"""Official evaluation script for SQuAD version 2.0.
+
+In addition to basic functionality, we also compute additional statistics and
+plot precision-recall curves if an additional na_prob.json file is provided.
+This file is expected to map question ID's to the model's predicted probability
+that a question is unanswerable.
+"""
+import argparse
+import collections
+import json
+import os
+import re
+import string
+import sys
+
+import numpy as np
+
+
+OPTS = None
+
+
+def parse_args():
+    parser = argparse.ArgumentParser("Official evaluation script for SQuAD version 2.0.")
+    parser.add_argument("data_file", metavar="data.json", help="Input data JSON file.")
+    parser.add_argument("pred_file", metavar="pred.json", help="Model predictions.")
+    parser.add_argument(
+        "--out-file", "-o", metavar="eval.json", help="Write accuracy metrics to file (default is stdout)."
+    )
+    parser.add_argument(
+        "--na-prob-file", "-n", metavar="na_prob.json", help="Model estimates of probability of no answer."
+    )
+    parser.add_argument(
+        "--na-prob-thresh",
+        "-t",
+        type=float,
+        default=1.0,
+        help='Predict "" if no-answer probability exceeds this (default = 1.0).',
+    )
+    parser.add_argument(
+        "--out-image-dir", "-p", metavar="out_images", default=None, help="Save precision-recall curves to directory."
+    )
+    parser.add_argument("--verbose", "-v", action="store_true")
+    if len(sys.argv) == 1:
+        parser.print_help()
+        sys.exit(1)
+    return parser.parse_args()
+
+
+def make_qid_to_has_ans(dataset):
+    qid_to_has_ans = {}
+    for article in dataset:
+        for p in article["paragraphs"]:
+            for qa in p["qas"]:
+                qid_to_has_ans[qa["id"]] = bool(qa["answers"]["text"])
+    return qid_to_has_ans
+
+
+def normalize_answer(s):
+    """Lower text and remove punctuation, articles and extra whitespace."""
+
+    def remove_articles(text):
+        regex = re.compile(r"\b(a|an|the)\b", re.UNICODE)
+        return re.sub(regex, " ", text)
+
+    def white_space_fix(text):
+        return " ".join(text.split())
+
+    def remove_punc(text):
+        exclude = set(string.punctuation)
+        return "".join(ch for ch in text if ch not in exclude)
+
+    def lower(text):
+        return text.lower()
+
+    return white_space_fix(remove_articles(remove_punc(lower(s))))
+
+
+def get_tokens(s):
+    if not s:
+        return []
+    return normalize_answer(s).split()
+
+
+def compute_exact(a_gold, a_pred):
+    return int(normalize_answer(a_gold) == normalize_answer(a_pred))
+
+
+def compute_f1(a_gold, a_pred):
+    gold_toks = get_tokens(a_gold)
+    pred_toks = get_tokens(a_pred)
+    common = collections.Counter(gold_toks) & collections.Counter(pred_toks)
+    num_same = sum(common.values())
+    if len(gold_toks) == 0 or len(pred_toks) == 0:
+        # If either is no-answer, then F1 is 1 if they agree, 0 otherwise
+        return int(gold_toks == pred_toks)
+    if num_same == 0:
+        return 0
+    precision = 1.0 * num_same / len(pred_toks)
+    recall = 1.0 * num_same / len(gold_toks)
+    f1 = (2 * precision * recall) / (precision + recall)
+    return f1
+
+
+def get_raw_scores(dataset, preds):
+    exact_scores = {}
+    f1_scores = {}
+    for article in dataset:
+        for p in article["paragraphs"]:
+            for qa in p["qas"]:
+                qid = qa["id"]
+                gold_answers = [t for t in qa["answers"]["text"] if normalize_answer(t)]
+                if not gold_answers:
+                    # For unanswerable questions, only correct answer is empty string
+                    gold_answers = [""]
+                if qid not in preds:
+                    print("Missing prediction for %s" % qid)
+                    continue
+                a_pred = preds[qid]
+                # Take max over all gold answers
+                exact_scores[qid] = max(compute_exact(a, a_pred) for a in gold_answers)
+                f1_scores[qid] = max(compute_f1(a, a_pred) for a in gold_answers)
+    return exact_scores, f1_scores
+
+
+def apply_no_ans_threshold(scores, na_probs, qid_to_has_ans, na_prob_thresh):
+    new_scores = {}
+    for qid, s in scores.items():
+        pred_na = na_probs[qid] > na_prob_thresh
+        if pred_na:
+            new_scores[qid] = float(not qid_to_has_ans[qid])
+        else:
+            new_scores[qid] = s
+    return new_scores
+
+
+def make_eval_dict(exact_scores, f1_scores, qid_list=None):
+    if not qid_list:
+        total = len(exact_scores)
+        return collections.OrderedDict(
+            [
+                ("exact", 100.0 * sum(exact_scores.values()) / total),
+                ("f1", 100.0 * sum(f1_scores.values()) / total),
+                ("total", total),
+            ]
+        )
+    else:
+        total = len(qid_list)
+        return collections.OrderedDict(
+            [
+                ("exact", 100.0 * sum(exact_scores[k] for k in qid_list) / total),
+                ("f1", 100.0 * sum(f1_scores[k] for k in qid_list) / total),
+                ("total", total),
+            ]
+        )
+
+
+def merge_eval(main_eval, new_eval, prefix):
+    for k in new_eval:
+        main_eval["%s_%s" % (prefix, k)] = new_eval[k]
+
+
+def plot_pr_curve(precisions, recalls, out_image, title):
+    plt.step(recalls, precisions, color="b", alpha=0.2, where="post")
+    plt.fill_between(recalls, precisions, step="post", alpha=0.2, color="b")
+    plt.xlabel("Recall")
+    plt.ylabel("Precision")
+    plt.xlim([0.0, 1.05])
+    plt.ylim([0.0, 1.05])
+    plt.title(title)
+    plt.savefig(out_image)
+    plt.clf()
+
+
+def make_precision_recall_eval(scores, na_probs, num_true_pos, qid_to_has_ans, out_image=None, title=None):
+    qid_list = sorted(na_probs, key=lambda k: na_probs[k])
+    true_pos = 0.0
+    cur_p = 1.0
+    cur_r = 0.0
+    precisions = [1.0]
+    recalls = [0.0]
+    avg_prec = 0.0
+    for i, qid in enumerate(qid_list):
+        if qid_to_has_ans[qid]:
+            true_pos += scores[qid]
+        cur_p = true_pos / float(i + 1)
+        cur_r = true_pos / float(num_true_pos)
+        if i == len(qid_list) - 1 or na_probs[qid] != na_probs[qid_list[i + 1]]:
+            # i.e., if we can put a threshold after this point
+            avg_prec += cur_p * (cur_r - recalls[-1])
+            precisions.append(cur_p)
+            recalls.append(cur_r)
+    if out_image:
+        plot_pr_curve(precisions, recalls, out_image, title)
+    return {"ap": 100.0 * avg_prec}
+
+
+def run_precision_recall_analysis(main_eval, exact_raw, f1_raw, na_probs, qid_to_has_ans, out_image_dir):
+    if out_image_dir and not os.path.exists(out_image_dir):
+        os.makedirs(out_image_dir)
+    num_true_pos = sum(1 for v in qid_to_has_ans.values() if v)
+    if num_true_pos == 0:
+        return
+    pr_exact = make_precision_recall_eval(
+        exact_raw,
+        na_probs,
+        num_true_pos,
+        qid_to_has_ans,
+        out_image=os.path.join(out_image_dir, "pr_exact.png"),
+        title="Precision-Recall curve for Exact Match score",
+    )
+    pr_f1 = make_precision_recall_eval(
+        f1_raw,
+        na_probs,
+        num_true_pos,
+        qid_to_has_ans,
+        out_image=os.path.join(out_image_dir, "pr_f1.png"),
+        title="Precision-Recall curve for F1 score",
+    )
+    oracle_scores = {k: float(v) for k, v in qid_to_has_ans.items()}
+    pr_oracle = make_precision_recall_eval(
+        oracle_scores,
+        na_probs,
+        num_true_pos,
+        qid_to_has_ans,
+        out_image=os.path.join(out_image_dir, "pr_oracle.png"),
+        title="Oracle Precision-Recall curve (binary task of HasAns vs. NoAns)",
+    )
+    merge_eval(main_eval, pr_exact, "pr_exact")
+    merge_eval(main_eval, pr_f1, "pr_f1")
+    merge_eval(main_eval, pr_oracle, "pr_oracle")
+
+
+def histogram_na_prob(na_probs, qid_list, image_dir, name):
+    if not qid_list:
+        return
+    x = [na_probs[k] for k in qid_list]
+    weights = np.ones_like(x) / float(len(x))
+    plt.hist(x, weights=weights, bins=20, range=(0.0, 1.0))
+    plt.xlabel("Model probability of no-answer")
+    plt.ylabel("Proportion of dataset")
+    plt.title("Histogram of no-answer probability: %s" % name)
+    plt.savefig(os.path.join(image_dir, "na_prob_hist_%s.png" % name))
+    plt.clf()
+
+
+def find_best_thresh(preds, scores, na_probs, qid_to_has_ans):
+    num_no_ans = sum(1 for k in qid_to_has_ans if not qid_to_has_ans[k])
+    cur_score = num_no_ans
+    best_score = cur_score
+    best_thresh = 0.0
+    qid_list = sorted(na_probs, key=lambda k: na_probs[k])
+    for i, qid in enumerate(qid_list):
+        if qid not in scores:
+            continue
+        if qid_to_has_ans[qid]:
+            diff = scores[qid]
+        else:
+            if preds[qid]:
+                diff = -1
+            else:
+                diff = 0
+        cur_score += diff
+        if cur_score > best_score:
+            best_score = cur_score
+            best_thresh = na_probs[qid]
+    return 100.0 * best_score / len(scores), best_thresh
+
+
+def find_all_best_thresh(main_eval, preds, exact_raw, f1_raw, na_probs, qid_to_has_ans):
+    best_exact, exact_thresh = find_best_thresh(preds, exact_raw, na_probs, qid_to_has_ans)
+    best_f1, f1_thresh = find_best_thresh(preds, f1_raw, na_probs, qid_to_has_ans)
+    main_eval["best_exact"] = best_exact
+    main_eval["best_exact_thresh"] = exact_thresh
+    main_eval["best_f1"] = best_f1
+    main_eval["best_f1_thresh"] = f1_thresh
+
+
+def main():
+    with open(OPTS.data_file) as f:
+        dataset_json = json.load(f)
+        dataset = dataset_json["data"]
+    with open(OPTS.pred_file) as f:
+        preds = json.load(f)
+    if OPTS.na_prob_file:
+        with open(OPTS.na_prob_file) as f:
+            na_probs = json.load(f)
+    else:
+        na_probs = {k: 0.0 for k in preds}
+    qid_to_has_ans = make_qid_to_has_ans(dataset)  # maps qid to True/False
+    has_ans_qids = [k for k, v in qid_to_has_ans.items() if v]
+    no_ans_qids = [k for k, v in qid_to_has_ans.items() if not v]
+    exact_raw, f1_raw = get_raw_scores(dataset, preds)
+    exact_thresh = apply_no_ans_threshold(exact_raw, na_probs, qid_to_has_ans, OPTS.na_prob_thresh)
+    f1_thresh = apply_no_ans_threshold(f1_raw, na_probs, qid_to_has_ans, OPTS.na_prob_thresh)
+    out_eval = make_eval_dict(exact_thresh, f1_thresh)
+    if has_ans_qids:
+        has_ans_eval = make_eval_dict(exact_thresh, f1_thresh, qid_list=has_ans_qids)
+        merge_eval(out_eval, has_ans_eval, "HasAns")
+    if no_ans_qids:
+        no_ans_eval = make_eval_dict(exact_thresh, f1_thresh, qid_list=no_ans_qids)
+        merge_eval(out_eval, no_ans_eval, "NoAns")
+    if OPTS.na_prob_file:
+        find_all_best_thresh(out_eval, preds, exact_raw, f1_raw, na_probs, qid_to_has_ans)
+    if OPTS.na_prob_file and OPTS.out_image_dir:
+        run_precision_recall_analysis(out_eval, exact_raw, f1_raw, na_probs, qid_to_has_ans, OPTS.out_image_dir)
+        histogram_na_prob(na_probs, has_ans_qids, OPTS.out_image_dir, "hasAns")
+        histogram_na_prob(na_probs, no_ans_qids, OPTS.out_image_dir, "noAns")
+    if OPTS.out_file:
+        with open(OPTS.out_file, "w") as f:
+            json.dump(out_eval, f)
+    else:
+        print(json.dumps(out_eval, indent=2))
+
+
+if __name__ == "__main__":
+    OPTS = parse_args()
+    if OPTS.out_image_dir:
+        import matplotlib
+
+        matplotlib.use("Agg")
+        import matplotlib.pyplot as plt
+    main()

examples/question-answering/squad_v2_local/squad_v2_local.py

@@ -0,0 +1,128 @@
+# coding=utf-8
+# Copyright 2020 The HuggingFace Datasets Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+""" SQuAD v2 metric. """
+
+import datasets
+
+from .evaluate import (
+    apply_no_ans_threshold,
+    find_all_best_thresh,
+    get_raw_scores,
+    make_eval_dict,
+    make_qid_to_has_ans,
+    merge_eval,
+)
+
+
+_CITATION = """\
+@inproceedings{Rajpurkar2016SQuAD10,
+  title={SQuAD: 100, 000+ Questions for Machine Comprehension of Text},
+  author={Pranav Rajpurkar and Jian Zhang and Konstantin Lopyrev and Percy Liang},
+  booktitle={EMNLP},
+  year={2016}
+}
+"""
+
+_DESCRIPTION = """
+This metric wrap the official scoring script for version 2 of the Stanford Question
+Answering Dataset (SQuAD).
+
+Stanford Question Answering Dataset (SQuAD) is a reading comprehension dataset, consisting of questions posed by
+crowdworkers on a set of Wikipedia articles, where the answer to every question is a segment of text, or span,
+from the corresponding reading passage, or the question might be unanswerable.
+
+SQuAD2.0 combines the 100,000 questions in SQuAD1.1 with over 50,000 unanswerable questions
+written adversarially by crowdworkers to look similar to answerable ones.
+To do well on SQuAD2.0, systems must not only answer questions when possible, but also
+determine when no answer is supported by the paragraph and abstain from answering.
+"""
+
+_KWARGS_DESCRIPTION = """
+Computes SQuAD v2 scores (F1 and EM).
+Args:
+    predictions: List of triple for question-answers to score with the following elements:
+        - the question-answer 'id' field as given in the references (see below)
+        - the text of the answer
+        - the probability that the question has no answer
+    references: List of question-answers dictionaries with the following key-values:
+            - 'id': id of the question-answer pair (see above),
+            - 'answers': a list of Dict {'text': text of the answer as a string}
+    no_answer_threshold: float
+        Probability threshold to decide that a question has no answer.
+Returns:
+    'exact': Exact match (the normalized answer exactly match the gold answer)
+    'f1': The F-score of predicted tokens versus the gold answer
+    'total': Number of score considered
+    'HasAns_exact': Exact match (the normalized answer exactly match the gold answer)
+    'HasAns_f1': The F-score of predicted tokens versus the gold answer
+    'HasAns_total': Number of score considered
+    'NoAns_exact': Exact match (the normalized answer exactly match the gold answer)
+    'NoAns_f1': The F-score of predicted tokens versus the gold answer
+    'NoAns_total': Number of score considered
+    'best_exact': Best exact match (with varying threshold)
+    'best_exact_thresh': No-answer probability threshold associated to the best exact match
+    'best_f1': Best F1 (with varying threshold)
+    'best_f1_thresh': No-answer probability threshold associated to the best F1
+"""
+
+
+class SquadV2(datasets.Metric):
+    def _info(self):
+        return datasets.MetricInfo(
+            description=_DESCRIPTION,
+            citation=_CITATION,
+            inputs_description=_KWARGS_DESCRIPTION,
+            features=datasets.Features(
+                {
+                    "predictions": {
+                        "id": datasets.Value("string"),
+                        "prediction_text": datasets.Value("string"),
+                        "no_answer_probability": datasets.Value("float32"),
+                    },
+                    "references": {
+                        "id": datasets.Value("string"),
+                        "answers": datasets.features.Sequence(
+                            {"text": datasets.Value("string"), "answer_start": datasets.Value("int32")}
+                        ),
+                    },
+                }
+            ),
+            codebase_urls=["https://rajpurkar.github.io/SQuAD-explorer/"],
+            reference_urls=["https://rajpurkar.github.io/SQuAD-explorer/"],
+        )
+
+    def _compute(self, predictions, references, no_answer_threshold=1.0):
+        no_answer_probabilities = dict((p["id"], p["no_answer_probability"]) for p in predictions)
+        dataset = [{"paragraphs": [{"qas": references}]}]
+        predictions = dict((p["id"], p["prediction_text"]) for p in predictions)
+
+        qid_to_has_ans = make_qid_to_has_ans(dataset)  # maps qid to True/False
+        has_ans_qids = [k for k, v in qid_to_has_ans.items() if v]
+        no_ans_qids = [k for k, v in qid_to_has_ans.items() if not v]
+
+        exact_raw, f1_raw = get_raw_scores(dataset, predictions)
+        exact_thresh = apply_no_ans_threshold(exact_raw, no_answer_probabilities, qid_to_has_ans, no_answer_threshold)
+        f1_thresh = apply_no_ans_threshold(f1_raw, no_answer_probabilities, qid_to_has_ans, no_answer_threshold)
+        out_eval = make_eval_dict(exact_thresh, f1_thresh)
+
+        if has_ans_qids:
+            has_ans_eval = make_eval_dict(exact_thresh, f1_thresh, qid_list=has_ans_qids)
+            merge_eval(out_eval, has_ans_eval, "HasAns")
+        if no_ans_qids:
+            no_ans_eval = make_eval_dict(exact_thresh, f1_thresh, qid_list=no_ans_qids)
+            merge_eval(out_eval, no_ans_eval, "NoAns")
+        find_all_best_thresh(out_eval, predictions, exact_raw, f1_raw, no_answer_probabilities, qid_to_has_ans)
+
+        return out_eval

examples/question-answering/trainer_qa.py

@@ -0,0 +1,104 @@
+# coding=utf-8
+# Copyright 2020 The HuggingFace Team All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""
+A subclass of `Trainer` specific to Question-Answering tasks
+"""
+
+from transformers import Trainer, is_datasets_available, is_torch_tpu_available
+from transformers.trainer_utils import PredictionOutput
+
+
+if is_datasets_available():
+    import datasets
+
+if is_torch_tpu_available():
+    import torch_xla.core.xla_model as xm
+    import torch_xla.debug.metrics as met
+
+
+class QuestionAnsweringTrainer(Trainer):
+    def __init__(self, *args, eval_examples=None, post_process_function=None, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.eval_examples = eval_examples
+        self.post_process_function = post_process_function
+
+    def evaluate(self, eval_dataset=None, eval_examples=None, ignore_keys=None):
+        eval_dataset = self.eval_dataset if eval_dataset is None else eval_dataset
+        eval_dataloader = self.get_eval_dataloader(eval_dataset)
+        eval_examples = self.eval_examples if eval_examples is None else eval_examples
+
+        # Temporarily disable metric computation, we will do it in the loop here.
+        compute_metrics = self.compute_metrics
+        self.compute_metrics = None
+        try:
+            output = self.prediction_loop(
+                eval_dataloader,
+                description="Evaluation",
+                # No point gathering the predictions if there are no metrics, otherwise we defer to
+                # self.args.prediction_loss_only
+                prediction_loss_only=True if compute_metrics is None else None,
+                ignore_keys=ignore_keys,
+            )
+        finally:
+            self.compute_metrics = compute_metrics
+
+        # We might have removed columns from the dataset so we put them back.
+        if isinstance(eval_dataset, datasets.Dataset):
+            eval_dataset.set_format(type=eval_dataset.format["type"], columns=list(eval_dataset.features.keys()))
+
+        if self.post_process_function is not None and self.compute_metrics is not None:
+            eval_preds = self.post_process_function(eval_examples, eval_dataset, output.predictions)
+            metrics = self.compute_metrics(eval_preds)
+
+            self.log(metrics)
+        else:
+            metrics = {}
+
+        if self.args.tpu_metrics_debug or self.args.debug:
+            # tpu-comment: Logging debug metrics for PyTorch/XLA (compile, execute times, ops, etc.)
+            xm.master_print(met.metrics_report())
+
+        self.control = self.callback_handler.on_evaluate(self.args, self.state, self.control, metrics)
+        return metrics
+
+    def predict(self, test_dataset, test_examples, ignore_keys=None):
+        test_dataloader = self.get_test_dataloader(test_dataset)
+
+        # Temporarily disable metric computation, we will do it in the loop here.
+        compute_metrics = self.compute_metrics
+        self.compute_metrics = None
+        try:
+            output = self.prediction_loop(
+                test_dataloader,
+                description="Evaluation",
+                # No point gathering the predictions if there are no metrics, otherwise we defer to
+                # self.args.prediction_loss_only
+                prediction_loss_only=True if compute_metrics is None else None,
+                ignore_keys=ignore_keys,
+            )
+        finally:
+            self.compute_metrics = compute_metrics
+
+        if self.post_process_function is None or self.compute_metrics is None:
+            return output
+
+        # We might have removed columns from the dataset so we put them back.
+        if isinstance(test_dataset, datasets.Dataset):
+            test_dataset.set_format(type=test_dataset.format["type"], columns=list(test_dataset.features.keys()))
+
+        eval_preds = self.post_process_function(test_examples, test_dataset, output.predictions)
+        metrics = self.compute_metrics(eval_preds)
+
+        return PredictionOutput(predictions=eval_preds.predictions, label_ids=eval_preds.label_ids, metrics=metrics)

examples/question-answering/utils_qa.py

@@ -0,0 +1,427 @@
+# coding=utf-8
+# Copyright 2020 The HuggingFace Team All rights reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+"""
+Post-processing utilities for question answering.
+"""
+import collections
+import json
+import logging
+import os
+from typing import Optional, Tuple
+
+import numpy as np
+from tqdm.auto import tqdm
+
+
+logger = logging.getLogger(__name__)
+
+
+def postprocess_qa_predictions(
+    examples,
+    features,
+    predictions: Tuple[np.ndarray, np.ndarray],
+    version_2_with_negative: bool = False,
+    n_best_size: int = 20,
+    max_answer_length: int = 30,
+    null_score_diff_threshold: float = 0.0,
+    output_dir: Optional[str] = None,
+    prefix: Optional[str] = None,
+    is_world_process_zero: bool = True,
+):
+    """
+    Post-processes the predictions of a question-answering model to convert them to answers that are substrings of the
+    original contexts. This is the base postprocessing functions for models that only return start and end logits.
+
+    Args:
+        examples: The non-preprocessed dataset (see the main script for more information).
+        features: The processed dataset (see the main script for more information).
+        predictions (:obj:`Tuple[np.ndarray, np.ndarray]`):
+            The predictions of the model: two arrays containing the start logits and the end logits respectively. Its
+            first dimension must match the number of elements of :obj:`features`.
+        version_2_with_negative (:obj:`bool`, `optional`, defaults to :obj:`False`):
+            Whether or not the underlying dataset contains examples with no answers.
+        n_best_size (:obj:`int`, `optional`, defaults to 20):
+            The total number of n-best predictions to generate when looking for an answer.
+        max_answer_length (:obj:`int`, `optional`, defaults to 30):
+            The maximum length of an answer that can be generated. This is needed because the start and end predictions
+            are not conditioned on one another.
+        null_score_diff_threshold (:obj:`float`, `optional`, defaults to 0):
+            The threshold used to select the null answer: if the best answer has a score that is less than the score of
+            the null answer minus this threshold, the null answer is selected for this example (note that the score of
+            the null answer for an example giving several features is the minimum of the scores for the null answer on
+            each feature: all features must be aligned on the fact they `want` to predict a null answer).
+
+            Only useful when :obj:`version_2_with_negative` is :obj:`True`.
+        output_dir (:obj:`str`, `optional`):
+            If provided, the dictionaries of predictions, n_best predictions (with their scores and logits) and, if
+            :obj:`version_2_with_negative=True`, the dictionary of the scores differences between best and null
+            answers, are saved in `output_dir`.
+        prefix (:obj:`str`, `optional`):
+            If provided, the dictionaries mentioned above are saved with `prefix` added to their names.
+        is_world_process_zero (:obj:`bool`, `optional`, defaults to :obj:`True`):
+            Whether this process is the main process or not (used to determine if logging/saves should be done).
+    """
+    assert len(predictions) == 2, "`predictions` should be a tuple with two elements (start_logits, end_logits)."
+    all_start_logits, all_end_logits = predictions
+
+    assert len(predictions[0]) == len(features), f"Got {len(predictions[0])} predictions and {len(features)} features."
+
+    # Build a map example to its corresponding features.
+    example_id_to_index = {k: i for i, k in enumerate(examples["id"])}
+    features_per_example = collections.defaultdict(list)
+    for i, feature in enumerate(features):
+        features_per_example[example_id_to_index[feature["example_id"]]].append(i)
+
+    # The dictionaries we have to fill.
+    all_predictions = collections.OrderedDict()
+    all_nbest_json = collections.OrderedDict()
+    if version_2_with_negative:
+        scores_diff_json = collections.OrderedDict()
+
+    # Logging.
+    logger.setLevel(logging.INFO if is_world_process_zero else logging.WARN)
+    logger.info(f"Post-processing {len(examples)} example predictions split into {len(features)} features.")
+
+    # Let's loop over all the examples!
+    for example_index, example in enumerate(tqdm(examples)):
+        # Those are the indices of the features associated to the current example.
+        feature_indices = features_per_example[example_index]
+
+        min_null_prediction = None
+        prelim_predictions = []
+
+        # Looping through all the features associated to the current example.
+        for feature_index in feature_indices:
+            # We grab the predictions of the model for this feature.
+            start_logits = all_start_logits[feature_index]
+            end_logits = all_end_logits[feature_index]
+            # This is what will allow us to map some the positions in our logits to span of texts in the original
+            # context.
+            offset_mapping = features[feature_index]["offset_mapping"]
+            # Optional `token_is_max_context`, if provided we will remove answers that do not have the maximum context
+            # available in the current feature.
+            token_is_max_context = features[feature_index].get("token_is_max_context", None)
+
+            # Update minimum null prediction.
+            feature_null_score = start_logits[0] + end_logits[0]
+            if min_null_prediction is None or min_null_prediction["score"] > feature_null_score:
+                min_null_prediction = {
+                    "offsets": (0, 0),
+                    "score": feature_null_score,
+                    "start_logit": start_logits[0],
+                    "end_logit": end_logits[0],
+                }
+
+            # Go through all possibilities for the `n_best_size` greater start and end logits.
+            start_indexes = np.argsort(start_logits)[-1 : -n_best_size - 1 : -1].tolist()
+            end_indexes = np.argsort(end_logits)[-1 : -n_best_size - 1 : -1].tolist()
+            for start_index in start_indexes:
+                for end_index in end_indexes:
+                    # Don't consider out-of-scope answers, either because the indices are out of bounds or correspond
+                    # to part of the input_ids that are not in the context.
+                    if (
+                        start_index >= len(offset_mapping)
+                        or end_index >= len(offset_mapping)
+                        or offset_mapping[start_index] is None
+                        or offset_mapping[end_index] is None
+                    ):
+                        continue
+                    # Don't consider answers with a length that is either < 0 or > max_answer_length.
+                    if end_index < start_index or end_index - start_index + 1 > max_answer_length:
+                        continue
+                    # Don't consider answer that don't have the maximum context available (if such information is
+                    # provided).
+                    if token_is_max_context is not None and not token_is_max_context.get(str(start_index), False):
+                        continue
+                    prelim_predictions.append(
+                        {
+                            "offsets": (offset_mapping[start_index][0], offset_mapping[end_index][1]),
+                            "score": start_logits[start_index] + end_logits[end_index],
+                            "start_logit": start_logits[start_index],
+                            "end_logit": end_logits[end_index],
+                        }
+                    )
+        if version_2_with_negative:
+            # Add the minimum null prediction
+            prelim_predictions.append(min_null_prediction)
+            null_score = min_null_prediction["score"]
+
+        # Only keep the best `n_best_size` predictions.
+        predictions = sorted(prelim_predictions, key=lambda x: x["score"], reverse=True)[:n_best_size]
+
+        # Add back the minimum null prediction if it was removed because of its low score.
+        if version_2_with_negative and not any(p["offsets"] == (0, 0) for p in predictions):
+            predictions.append(min_null_prediction)
+
+        # Use the offsets to gather the answer text in the original context.
+        context = example["context"]
+        for pred in predictions:
+            offsets = pred.pop("offsets")
+            pred["text"] = context[offsets[0] : offsets[1]]
+
+        # In the very rare edge case we have not a single non-null prediction, we create a fake prediction to avoid
+        # failure.
+        if len(predictions) == 0 or (len(predictions) == 1 and predictions[0]["text"] == ""):
+            predictions.insert(0, {"text": "empty", "start_logit": 0.0, "end_logit": 0.0, "score": 0.0})
+
+        # Compute the softmax of all scores (we do it with numpy to stay independent from torch/tf in this file, using
+        # the LogSumExp trick).
+        scores = np.array([pred.pop("score") for pred in predictions])
+        exp_scores = np.exp(scores - np.max(scores))
+        probs = exp_scores / exp_scores.sum()
+
+        # Include the probabilities in our predictions.
+        for prob, pred in zip(probs, predictions):
+            pred["probability"] = prob
+
+        # Pick the best prediction. If the null answer is not possible, this is easy.
+        if not version_2_with_negative:
+            all_predictions[example["id"]] = predictions[0]["text"]
+        else:
+            # Otherwise we first need to find the best non-empty prediction.
+            i = 0
+            while predictions[i]["text"] == "":
+                i += 1
+            best_non_null_pred = predictions[i]
+
+            # Then we compare to the null prediction using the threshold.
+            score_diff = null_score - best_non_null_pred["start_logit"] - best_non_null_pred["end_logit"]
+            scores_diff_json[example["id"]] = float(score_diff)  # To be JSON-serializable.
+            if score_diff > null_score_diff_threshold:
+                all_predictions[example["id"]] = ""
+            else:
+                all_predictions[example["id"]] = best_non_null_pred["text"]
+
+        # Make `predictions` JSON-serializable by casting np.float back to float.
+        all_nbest_json[example["id"]] = [
+            {k: (float(v) if isinstance(v, (np.float16, np.float32, np.float64)) else v) for k, v in pred.items()}
+            for pred in predictions
+        ]
+
+    # If we have an output_dir, let's save all those dicts.
+    if output_dir is not None:
+        assert os.path.isdir(output_dir), f"{output_dir} is not a directory."
+
+        prediction_file = os.path.join(
+            output_dir, "predictions.json" if prefix is None else f"predictions_{prefix}".json
+        )
+        nbest_file = os.path.join(
+            output_dir, "nbest_predictions.json" if prefix is None else f"nbest_predictions_{prefix}".json
+        )
+        if version_2_with_negative:
+            null_odds_file = os.path.join(
+                output_dir, "null_odds.json" if prefix is None else f"null_odds_{prefix}".json
+            )
+
+        logger.info(f"Saving predictions to {prediction_file}.")
+        with open(prediction_file, "w") as writer:
+            writer.write(json.dumps(all_predictions, indent=4) + "\n")
+        logger.info(f"Saving nbest_preds to {nbest_file}.")
+        with open(nbest_file, "w") as writer:
+            writer.write(json.dumps(all_nbest_json, indent=4) + "\n")
+        if version_2_with_negative:
+            logger.info(f"Saving null_odds to {null_odds_file}.")
+            with open(null_odds_file, "w") as writer:
+                writer.write(json.dumps(scores_diff_json, indent=4) + "\n")
+
+    return all_predictions
+
+
+def postprocess_qa_predictions_with_beam_search(
+    examples,
+    features,
+    predictions: Tuple[np.ndarray, np.ndarray],
+    version_2_with_negative: bool = False,
+    n_best_size: int = 20,
+    max_answer_length: int = 30,
+    start_n_top: int = 5,
+    end_n_top: int = 5,
+    output_dir: Optional[str] = None,
+    prefix: Optional[str] = None,
+    is_world_process_zero: bool = True,
+):
+    """
+    Post-processes the predictions of a question-answering model with beam search to convert them to answers that are substrings of the
+    original contexts. This is the postprocessing functions for models that return start and end logits, indices, as well as
+    cls token predictions.
+
+    Args:
+        examples: The non-preprocessed dataset (see the main script for more information).
+        features: The processed dataset (see the main script for more information).
+        predictions (:obj:`Tuple[np.ndarray, np.ndarray]`):
+            The predictions of the model: two arrays containing the start logits and the end logits respectively. Its
+            first dimension must match the number of elements of :obj:`features`.
+        version_2_with_negative (:obj:`bool`, `optional`, defaults to :obj:`False`):
+            Whether or not the underlying dataset contains examples with no answers.
+        n_best_size (:obj:`int`, `optional`, defaults to 20):
+            The total number of n-best predictions to generate when looking for an answer.
+        max_answer_length (:obj:`int`, `optional`, defaults to 30):
+            The maximum length of an answer that can be generated. This is needed because the start and end predictions
+            are not conditioned on one another.
+        start_n_top (:obj:`int`, `optional`, defaults to 5):
+            The number of top start logits too keep when searching for the :obj:`n_best_size` predictions.
+        end_n_top (:obj:`int`, `optional`, defaults to 5):
+            The number of top end logits too keep when searching for the :obj:`n_best_size` predictions.
+        output_dir (:obj:`str`, `optional`):
+            If provided, the dictionaries of predictions, n_best predictions (with their scores and logits) and, if
+            :obj:`version_2_with_negative=True`, the dictionary of the scores differences between best and null
+            answers, are saved in `output_dir`.
+        prefix (:obj:`str`, `optional`):
+            If provided, the dictionaries mentioned above are saved with `prefix` added to their names.
+        is_world_process_zero (:obj:`bool`, `optional`, defaults to :obj:`True`):
+            Whether this process is the main process or not (used to determine if logging/saves should be done).
+    """
+    assert len(predictions) == 5, "`predictions` should be a tuple with five elements."
+    start_top_log_probs, start_top_index, end_top_log_probs, end_top_index, cls_logits = predictions
+
+    assert len(predictions[0]) == len(
+        features
+    ), f"Got {len(predictions[0])} predicitions and {len(features)} features."
+
+    # Build a map example to its corresponding features.
+    example_id_to_index = {k: i for i, k in enumerate(examples["id"])}
+    features_per_example = collections.defaultdict(list)
+    for i, feature in enumerate(features):
+        features_per_example[example_id_to_index[feature["example_id"]]].append(i)
+
+    # The dictionaries we have to fill.
+    all_predictions = collections.OrderedDict()
+    all_nbest_json = collections.OrderedDict()
+    scores_diff_json = collections.OrderedDict() if version_2_with_negative else None
+
+    # Logging.
+    logger.setLevel(logging.INFO if is_world_process_zero else logging.WARN)
+    logger.info(f"Post-processing {len(examples)} example predictions split into {len(features)} features.")
+
+    # Let's loop over all the examples!
+    for example_index, example in enumerate(tqdm(examples)):
+        # Those are the indices of the features associated to the current example.
+        feature_indices = features_per_example[example_index]
+
+        min_null_score = None
+        prelim_predictions = []
+
+        # Looping through all the features associated to the current example.
+        for feature_index in feature_indices:
+            # We grab the predictions of the model for this feature.
+            start_log_prob = start_top_log_probs[feature_index]
+            start_indexes = start_top_index[feature_index]
+            end_log_prob = end_top_log_probs[feature_index]
+            end_indexes = end_top_index[feature_index]
+            feature_null_score = cls_logits[feature_index]
+            # This is what will allow us to map some the positions in our logits to span of texts in the original
+            # context.
+            offset_mapping = features[feature_index]["offset_mapping"]
+            # Optional `token_is_max_context`, if provided we will remove answers that do not have the maximum context
+            # available in the current feature.
+            token_is_max_context = features[feature_index].get("token_is_max_context", None)
+
+            # Update minimum null prediction
+            if min_null_score is None or feature_null_score < min_null_score:
+                min_null_score = feature_null_score
+
+            # Go through all possibilities for the `n_start_top`/`n_end_top` greater start and end logits.
+            for i in range(start_n_top):
+                for j in range(end_n_top):
+                    start_index = start_indexes[i]
+                    j_index = i * end_n_top + j
+                    end_index = end_indexes[j_index]
+                    # Don't consider out-of-scope answers (last part of the test should be unnecessary because of the
+                    # p_mask but let's not take any risk)
+                    if (
+                        start_index >= len(offset_mapping)
+                        or end_index >= len(offset_mapping)
+                        or offset_mapping[start_index] is None
+                        or offset_mapping[end_index] is None
+                    ):
+                        continue
+                    # Don't consider answers with a length negative or > max_answer_length.
+                    if end_index < start_index or end_index - start_index + 1 > max_answer_length:
+                        continue
+                    # Don't consider answer that don't have the maximum context available (if such information is
+                    # provided).
+                    if token_is_max_context is not None and not token_is_max_context.get(str(start_index), False):
+                        continue
+                    prelim_predictions.append(
+                        {
+                            "offsets": (offset_mapping[start_index][0], offset_mapping[end_index][1]),
+                            "score": start_log_prob[i] + end_log_prob[j_index],
+                            "start_log_prob": start_log_prob[i],
+                            "end_log_prob": end_log_prob[j_index],
+                        }
+                    )
+
+        # Only keep the best `n_best_size` predictions.
+        predictions = sorted(prelim_predictions, key=lambda x: x["score"], reverse=True)[:n_best_size]
+
+        # Use the offsets to gather the answer text in the original context.
+        context = example["context"]
+        for pred in predictions:
+            offsets = pred.pop("offsets")
+            pred["text"] = context[offsets[0] : offsets[1]]
+
+        # In the very rare edge case we have not a single non-null prediction, we create a fake prediction to avoid
+        # failure.
+        if len(predictions) == 0:
+            predictions.insert(0, {"text": "", "start_logit": -1e-6, "end_logit": -1e-6, "score": -2e-6})
+
+        # Compute the softmax of all scores (we do it with numpy to stay independent from torch/tf in this file, using
+        # the LogSumExp trick).
+        scores = np.array([pred.pop("score") for pred in predictions])
+        exp_scores = np.exp(scores - np.max(scores))
+        probs = exp_scores / exp_scores.sum()
+
+        # Include the probabilities in our predictions.
+        for prob, pred in zip(probs, predictions):
+            pred["probability"] = prob
+
+        # Pick the best prediction and set the probability for the null answer.
+        all_predictions[example["id"]] = predictions[0]["text"]
+        if version_2_with_negative:
+            scores_diff_json[example["id"]] = float(min_null_score)
+
+        # Make `predictions` JSON-serializable by casting np.float back to float.
+        all_nbest_json[example["id"]] = [
+            {k: (float(v) if isinstance(v, (np.float16, np.float32, np.float64)) else v) for k, v in pred.items()}
+            for pred in predictions
+        ]
+
+    # If we have an output_dir, let's save all those dicts.
+    if output_dir is not None:
+        assert os.path.isdir(output_dir), f"{output_dir} is not a directory."
+
+        prediction_file = os.path.join(
+            output_dir, "predictions.json" if prefix is None else f"predictions_{prefix}".json
+        )
+        nbest_file = os.path.join(
+            output_dir, "nbest_predictions.json" if prefix is None else f"nbest_predictions_{prefix}".json
+        )
+        if version_2_with_negative:
+            null_odds_file = os.path.join(
+                output_dir, "null_odds.json" if prefix is None else f"null_odds_{prefix}".json
+            )
+
+        print(f"Saving predictions to {prediction_file}.")
+        with open(prediction_file, "w") as writer:
+            writer.write(json.dumps(all_predictions, indent=4) + "\n")
+        print(f"Saving nbest_preds to {nbest_file}.")
+        with open(nbest_file, "w") as writer:
+            writer.write(json.dumps(all_nbest_json, indent=4) + "\n")
+        if version_2_with_negative:
+            print(f"Saving null_odds to {null_odds_file}.")
+            with open(null_odds_file, "w") as writer:
+                writer.write(json.dumps(scores_diff_json, indent=4) + "\n")
+
+    return all_predictions, scores_diff_json