Merge pull request #268 from wangxiaodiu/master

fixed a minor bug in README.md

README.md

@@ -45,12 +45,14 @@ PyTorch pretrained bert can be installed by pip as follows:
 pip install pytorch-pretrained-bert
 ```
 
-If you want to use the tokenizer associated to the `OpenAI GPT` tokenizer, you will need to install `ftfy` (if you are using Python 2, version 4.4.3 is the last version working for you) and `SpaCy` :
+If you want to reproduce the original tokenization process of the `OpenAI GPT` paper, you will need to install `ftfy` (limit to version 4.4.3 if you are using Python 2) and `SpaCy` :
 ```bash
 pip install spacy ftfy==4.4.3
 python -m spacy download en
 ```
 
+If you don't install `ftfy` and `SpaCy`, the `OpenAI GPT` tokenizer will default to tokenize using BERT's `BasicTokenizer` followed by Byte-Pair Encoding (which should be fine for most usage, don't worry).
+
 ### From source
 
 Clone the repository and run:
@@ -58,12 +60,13 @@ Clone the repository and run:
 pip install [--editable] .
 ```
 
-Here also, if you want to use `OpenAIGPT` tokenizer, you will need to install `ftfy` (limit to version 4.4.3 if you are using Python 2) and `SpaCy` :
+Here also, if you want to reproduce the original tokenization process of the `OpenAI GPT` model, you will need to install `ftfy` (limit to version 4.4.3 if you are using Python 2) and `SpaCy` :
 ```bash
 pip install spacy ftfy==4.4.3
 python -m spacy download en
 ```
 
+Again, if you don't install `ftfy` and `SpaCy`, the `OpenAI GPT` tokenizer will default to tokenize using BERT's `BasicTokenizer` followed by Byte-Pair Encoding (which should be fine for most usage).
 
 A series of tests is included in the [tests folder](https://github.com/huggingface/pytorch-pretrained-BERT/tree/master/tests) and can be run using `pytest` (install pytest if needed: `pip install pytest`).
 
@@ -127,11 +130,10 @@ The repository further comprises:
   - [`run_lm_finetuning.py`](./examples/run_lm_finetuning.py) - Show how to fine-tune an instance of `BertForPretraining' on a target text corpus.  
 
 - One example on how to use **OpenAI GPT** (in the [`examples` folder](./examples)):
-  - [`openai_gpt_train.py`](./examples/openai_gpt_train.py) - Show how to fine-tune an instance of `OpenGPTDoubleHeadsModel` on the RocStories task.
+  - [`run_openai_gpt.py`](./examples/run_openai_gpt.py) - Show how to fine-tune an instance of `OpenGPTDoubleHeadsModel` on the RocStories task.
 
-- Two examples on how to use **Transformer-XL** (in the [`examples` folder](./examples)):
-  - [`transfo_xl_train.py`](./examples/transfo_xl_train.py) - Show how to train and exaluate an instance of `TransfoXLModel` on WikiText 103,
-  - [`transfo_xl_eval.py`](./examples/transfo_xl_eval.py) - Simply exaluate a pre-trained model of `TransfoXLModel` on WikiText 103.
+- One example on how to use **Transformer-XL** (in the [`examples` folder](./examples)):
+  - [`run_transfo_xl.py`](./examples/run_transfo_xl.py) - Show how to load and evaluate a pre-trained model of `TransfoXLLMHeadModel` on WikiText 103.
 
   These examples are detailed in the [Examples](#examples) section of this readme.
 
@@ -158,6 +160,10 @@ First let's prepare a tokenized input with `BertTokenizer`
 import torch
 from pytorch_pretrained_bert import BertTokenizer, BertModel, BertForMaskedLM
 
+# OPTIONAL: if you want to have more information on what's happening, activate the logger as follows
+import logging
+logging.basicConfig(level=logging.INFO)
+
 # Load pre-trained model tokenizer (vocabulary)
 tokenizer = BertTokenizer.from_pretrained('bert-base-uncased')
 
@@ -166,7 +172,7 @@ text = "[CLS] Who was Jim Henson ? [SEP] Jim Henson was a puppeteer [SEP]"
 tokenized_text = tokenizer.tokenize(text)
 
 # Mask a token that we will try to predict back with `BertForMaskedLM`
-masked_index = 6
+masked_index = 8
 tokenized_text[masked_index] = '[MASK]'
 assert tokenized_text == ['[CLS]', 'who', 'was', 'jim', 'henson', '?', '[SEP]', 'jim', '[MASK]', 'was', 'a', 'puppet', '##eer', '[SEP]']
 
@@ -231,6 +237,10 @@ First let's prepare a tokenized input with `OpenAIGPTTokenizer`
 import torch
 from pytorch_pretrained_bert import OpenAIGPTTokenizer, OpenAIGPTModel, OpenAIGPTLMHeadModel
 
+# OPTIONAL: if you want to have more information on what's happening, activate the logger as follows
+import logging
+logging.basicConfig(level=logging.INFO)
+
 # Load pre-trained model tokenizer (vocabulary)
 tokenizer = OpenAIGPTTokenizer.from_pretrained('openai-gpt')
 
@@ -292,6 +302,10 @@ First let's prepare a tokenized input with `TransfoXLTokenizer`
 import torch
 from pytorch_pretrained_bert import TransfoXLTokenizer, TransfoXLModel, TransfoXLLMHeadModel
 
+# OPTIONAL: if you want to have more information on what's happening, activate the logger as follows
+import logging
+logging.basicConfig(level=logging.INFO)
+
 # Load pre-trained model tokenizer (vocabulary from wikitext 103)
 tokenizer = TransfoXLTokenizer.from_pretrained('transfo-xl-wt103')
 
@@ -630,10 +644,12 @@ This model *outputs* a tuple of (last_hidden_state, new_mems)
 
 `BertTokenizer` perform end-to-end tokenization, i.e. basic tokenization followed by WordPiece tokenization.
 
-This class has two arguments:
+This class has four arguments:
 
 - `vocab_file`: path to a vocabulary file.
 - `do_lower_case`: convert text to lower-case while tokenizing. **Default = True**.
+- `max_len`: max length to filter the input of the Transformer. Default to pre-trained value for the model if `None`. **Default = None**
+- `never_split`: a list of tokens that should not be splitted during tokenization. **Default = `["[UNK]", "[SEP]", "[PAD]", "[CLS]", "[MASK]"]`**
 
 and three methods:
 
@@ -647,16 +663,20 @@ Please refer to the doc strings and code in [`tokenization.py`](./pytorch_pretra
 
 `OpenAIGPTTokenizer` perform Byte-Pair-Encoding (BPE) tokenization.
 
-This class has two arguments:
+This class has four arguments:
 
 - `vocab_file`: path to a vocabulary file.
 - `merges_file`: path to a file containing the BPE merges.
+- `max_len`: max length to filter the input of the Transformer. Default to pre-trained value for the model if `None`. **Default = None**
+- `special_tokens`: a list of tokens to add to the vocabulary for fine-tuning. If SpaCy is not installed and BERT's `BasicTokenizer` is used as the pre-BPE tokenizer, these tokens are not split. **Default= None**
 
-and three methods:
+and five methods:
 
 - `tokenize(text)`: convert a `str` in a list of `str` tokens by (1) performing basic tokenization and (2) WordPiece tokenization.
 - `convert_tokens_to_ids(tokens)`: convert a list of `str` tokens in a list of `int` indices in the vocabulary.
 - `convert_ids_to_tokens(tokens)`: convert a list of `int` indices in a list of `str` tokens in the vocabulary.
+- `set_special_tokens(self, special_tokens)`: update the list of special tokens (see above arguments)
+- `decode(ids, skip_special_tokens=False, clean_up_tokenization_spaces=False)`: decode a list of `int` indices in a string and do some post-processing if needed: (i) remove special tokens from the output and (ii) clean up tokenization spaces.
 
 Please refer to the doc strings and code in [`tokenization_openai.py`](./pytorch_pretrained_bert/tokenization_openai.py) for the details of the `OpenAIGPTTokenizer`.
 

pytorch_pretrained_bert/__init__.py

@@ -1,4 +1,4 @@
-__version__ = "0.5.0"
+__version__ = "0.5.1"
 from .tokenization import BertTokenizer, BasicTokenizer, WordpieceTokenizer
 from .tokenization_openai import OpenAIGPTTokenizer
 from .tokenization_transfo_xl import (TransfoXLTokenizer, TransfoXLCorpus)

pytorch_pretrained_bert/modeling_transfo_xl.py

@@ -959,7 +959,12 @@ class TransfoXLPreTrainedModel(nn.Module):
             for name, child in module._modules.items():
                 if child is not None:
                     load(child, prefix + name + '.')
-        load(model, prefix='')
+
+        start_prefix = ''
+        if not hasattr(model, 'transformer') and any(s.startswith('transformer.') for s in state_dict.keys()):
+            start_prefix = 'transformer.'
+        load(model, prefix=start_prefix)
+
         if len(missing_keys) > 0:
             logger.info("Weights of {} not initialized from pretrained model: {}".format(
                 model.__class__.__name__, missing_keys))

pytorch_pretrained_bert/tokenization_openai.py

@@ -26,6 +26,7 @@ from io import open
 from tqdm import tqdm
 
 from .file_utils import cached_path
+from .tokenization import BasicTokenizer
 
 logger = logging.getLogger(__name__)
 
@@ -72,8 +73,9 @@ class OpenAIGPTTokenizer(object):
     """
     BPE tokenizer. Peculiarities:
         - lower case all inputs
-        - uses SpaCy tokenizer
-        - special tokens: additional symbols (ex: "__classify__") to add to a vocabulary.
+        - uses SpaCy tokenizer and ftfy for pre-BPE tokenization if they are installed, fallback to BERT's BasicTokenizer if not.
+        - argument special_tokens and function set_special_tokens:
+            can be used to add additional symbols (ex: "__classify__") to a vocabulary.
     """
     @classmethod
     def from_pretrained(cls, pretrained_model_name_or_path, cache_dir=None, *inputs, **kwargs):
@@ -122,12 +124,15 @@ class OpenAIGPTTokenizer(object):
         try:
             import ftfy
             import spacy
+            self.nlp = spacy.load('en', disable=['parser', 'tagger', 'ner', 'textcat'])
+            self.fix_text = ftfy.fix_text
         except ImportError:
-            raise ImportError("Please install ftfy and spacy to use OpenAI GPT tokenizer.")
+            logger.warning("ftfy or spacy is not installed using BERT BasicTokenizer instead of SpaCy & ftfy.")
+            self.nlp = BasicTokenizer(do_lower_case=True,
+                                      never_split=special_tokens if special_tokens is not None else [])
+            self.fix_text = None
 
         self.max_len = max_len if max_len is not None else int(1e12)
-        self.nlp = spacy.load('en', disable=['parser', 'tagger', 'ner', 'textcat'])
-        self.fix_text = ftfy.fix_text
         self.encoder = json.load(open(vocab_file, encoding="utf-8"))
         self.decoder = {v:k for k,v in self.encoder.items()}
         merges = open(merges_file, encoding='utf-8').read().split('\n')[1:-1]
@@ -150,6 +155,9 @@ class OpenAIGPTTokenizer(object):
             return
         self.special_tokens = dict((tok, len(self.encoder) + i) for i, tok in enumerate(special_tokens))
         self.special_tokens_decoder = {v:k for k, v in self.special_tokens.items()}
+        if self.fix_text is None:
+            # Using BERT's BasicTokenizer: we can update the tokenizer
+            self.nlp.never_split = special_tokens
         logger.info("Special tokens {}".format(self.special_tokens))
 
     def bpe(self, token):
@@ -198,9 +206,16 @@ class OpenAIGPTTokenizer(object):
     def tokenize(self, text):
         """ Tokenize a string. """
         split_tokens = []
-        text = self.nlp(text_standardize(self.fix_text(text)))
-        for token in text:
-            split_tokens.extend([t for t in self.bpe(token.text.lower()).split(' ')])
+        if self.fix_text is None:
+            # Using BERT's BasicTokenizer
+            text = self.nlp.tokenize(text)
+            for token in text:
+                split_tokens.extend([t for t in self.bpe(token).split(' ')])
+        else:
+            # Using SpaCy & ftfy (original tokenization process of OpenAI GPT)
+            text = self.nlp(text_standardize(self.fix_text(text)))
+            for token in text:
+                split_tokens.extend([t for t in self.bpe(token.text.lower()).split(' ')])
         return split_tokens
 
     def convert_tokens_to_ids(self, tokens):
@@ -219,8 +234,8 @@ class OpenAIGPTTokenizer(object):
         if len(ids) > self.max_len:
             raise ValueError(
                 "Token indices sequence length is longer than the specified maximum "
-                " sequence length for this BERT model ({} > {}). Running this"
-                " sequence through BERT will result in indexing errors".format(len(ids), self.max_len)
+                " sequence length for this OpenAI GPT model ({} > {}). Running this"
+                " sequence through the model will result in indexing errors".format(len(ids), self.max_len)
             )
         return ids
 

setup.py

@@ -38,7 +38,7 @@ from setuptools import find_packages, setup
 
 setup(
     name="pytorch_pretrained_bert",
-    version="0.5.0",
+    version="0.5.1",
     author="Thomas Wolf, Victor Sanh, Tim Rault, Google AI Language Team Authors, Open AI team Authors",
     author_email="thomas@huggingface.co",
     description="PyTorch version of Google AI BERT model with script to load Google pre-trained models",