docs: def generate_text_files(in_dir, out_dir, include_header=False):
      """\
      Walks through the `in_dir` and generates text versions of
      the cables in the `out_dir`.
      """
      for cable in cables_from_source(in_dir):
          out = codecs.open(out_dir + '/' + cable.reference_id + '.txt', 'wb', encoding='utf-8')
          out.write(cable_to_text(cable, include_header))
          out.close()