def _maybe_download_corpora(tmp_dir):
  """Download corpora for multinli.

  Args:
    tmp_dir: a string
  Returns:
    a string
  """
  mnli_filename = "MNLI.zip"
  mnli_finalpath = os.path.join(tmp_dir, "MNLI")
  if not tf.gfile.Exists(mnli_finalpath):
    zip_filepath = generator_utils.maybe_download(
        tmp_dir, mnli_filename, _MNLI_URL)
    zip_ref = zipfile.ZipFile(zip_filepath, "r")
    zip_ref.extractall(tmp_dir)
    zip_ref.close()

  return mnli_finalpath
Download corpora for multinli.

  Args:
    tmp_dir: a string
  Returns:
    a string
  
tensor2tensor/data_generators/multinli.py