`translate_enzh_wmt8k` dev data path error

[zyshin]

> t2t-datagen \
>   --data_dir=$DATA_DIR \
>   --tmp_dir=$TMP_DIR \
>   --problem=$PROBLEM
INFO:tensorflow:Generating problems:
    translate:
      * translate_enzh_wmt8k
INFO:tensorflow:Generating data for translate_enzh_wmt8k.
INFO:tensorflow:Found vocab file: /home/translate/t2t_data/vocab.enzh-en.8192
INFO:tensorflow:Found vocab file: /home/translate/t2t_data/vocab.enzh-zh.8192
INFO:tensorflow:Not downloading, file already found: /tmp/t2t_datagen/training-parallel-nc-v12.tgz
INFO:tensorflow:Found vocab file: /home/translate/t2t_data/vocab.enzh-en.8192
INFO:tensorflow:Found vocab file: /home/translate/t2t_data/vocab.enzh-zh.8192
INFO:tensorflow:Not downloading, file already found: /tmp/t2t_datagen/dev.tgz
Traceback (most recent call last):
  File "/home/translate/env/bin/t2t-datagen", line 212, in <module>
    tf.app.run()
  File "/home/translate/env/lib/python3.5/site-packages/tensorflow/python/platform/app.py", line 48, in run
    _sys.exit(main(_sys.argv[:1] + flags_passthrough))
  File "/home/translate/env/bin/t2t-datagen", line 178, in main
    generate_data_for_registered_problem(problem)
  File "/home/translate/env/bin/t2t-datagen", line 208, in generate_data_for_registered_problem
    task_id=task_id)
  File "/home/translate/env/lib/python3.5/site-packages/tensor2tensor/data_generators/problem.py", line 638, in generate_data
    self.generator(data_dir, tmp_dir, False), dev_paths)
  File "/home/translate/env/lib/python3.5/site-packages/tensor2tensor/data_generators/translate_enzh.py", line 88, in generator
    "wmt_enzh_tok_%s" % tag)
  File "/home/translate/env/lib/python3.5/site-packages/tensor2tensor/data_generators/translate.py", line 246, in compile_data
    line1, line2 = lang1_file.readline(), lang2_file.readline()
  File "/home/translate/env/lib/python3.5/site-packages/tensorflow/python/lib/io/file_io.py", line 177, in readline
    self._preread_check()
  File "/home/translate/env/lib/python3.5/site-packages/tensorflow/python/lib/io/file_io.py", line 79, in _preread_check
    compat.as_bytes(self.__name), 1024 * 512, status)
  File "/home/translate/env/lib/python3.5/site-packages/tensorflow/python/framework/errors_impl.py", line 473, in __exit__
    c_api.TF_GetCode(self.status.status))
tensorflow.python.framework.errors_impl.NotFoundError: /tmp/t2t_datagen/dev/newsdev2017-zhen-src.en.sgm; No such file or directory

Changing line 52 of file data_generators/enzh_wmt8k.py from
dev/newsdev2017-zhen-src.en.sgm and dev/newsdev2017-zhen-ref.zh.sgm to
dev/newsdev2017-enzh-src.en.sgm and dev/newsdev2017-enzh-ref.zh.sgm
will make it work.

[rsepassi]

Ah, thank you. Would you like to submit a PR with the fix?

[zyshin]

Sure, already posted as #453

[rsepassi]

Thanks!