Add wmt translation example (#3428)

* add translation example

* make style

* adapt docstring

* add gpu device as input for example

* small renaming

* better README

examples/translation/t5/test_t5_examples.py

@@ -0,0 +1,28 @@
+import logging
+import sys
+import tempfile
+import unittest
+from pathlib import Path
+from unittest.mock import patch
+
+from .evaluate_wmt import run_generate
+
+
+text = [" New York (CNN)When Liana Barrientos was 23 years old, she got married in Westchester County."]
+
+logging.basicConfig(level=logging.DEBUG)
+
+logger = logging.getLogger()
+
+
+class TestT5Examples(unittest.TestCase):
+    def test_t5_cli(self):
+        stream_handler = logging.StreamHandler(sys.stdout)
+        logger.addHandler(stream_handler)
+        tmp = Path(tempfile.gettempdir()) / "utest_generations.hypo"
+        with tmp.open("w") as f:
+            f.write("\n".join(text))
+        testargs = ["evaluate_cnn.py", str(tmp), "output.txt", str(tmp), "score.txt"]
+        with patch.object(sys, "argv", testargs):
+            run_generate()
+            self.assertTrue(Path("output.txt").exists())