def get_or_generate_txt_vocab(data_dir, vocab_filename, vocab_size,
                              filepatterns):
  """Generate a vocabulary from txt files with example-per-line."""
  if isinstance(filepatterns, str):
    filepatterns = [filepatterns]

  def generate():
    tf.logging.info("Generating vocab from %s", filepatterns)
    for filepattern in filepatterns:
      for filename in tf.gfile.Glob(filepattern):
        with tf.gfile.GFile(filename, mode="r") as source_file:
          for line in source_file:
            yield line.strip()

  return get_or_generate_vocab_inner(data_dir, vocab_filename, vocab_size,
                                     generate())
Generate a vocabulary from txt files with example-per-line.