code: def write_raw_text_to_files(all_files, urls_path, dataset_split, tmp_dir):
    
  
    def write_to_file(all_files, urls_path, tmp_dir, filename):
      """Write text to files."""
      with io.open(
          os.path.join(tmp_dir, filename + ".source"), "w",
          encoding="utf-8") as fstory:
        with io.open(
            os.path.join(tmp_dir, filename + ".target"), "w",
            encoding="utf-8") as fsummary:
          for example in example_generator(all_files, urls_path, sum_token=True):
            story, summary = _story_summary_split(example)
            fstory.write(story + "\n")
            fsummary.write(summary + "\n")
  
    if dataset_split == problem.DatasetSplit.TRAIN:
      filename = "cnndm.train"
    elif dataset_split == problem.DatasetSplit.EVAL:
      filename = "cnndm.dev"
    else:
      filename = "cnndm.test"
  
    tf.logging.info("Writing %s" % filename)
    write_to_file(all_files, urls_path, tmp_dir, filename)
docs: Write text to files.