nodes: 0, module; 1, function_definition; 2, function_name:get_filenames; 3, parameters; 4, block; 5, identifier:dirname; 6, expression_statement; 7, expression_statement; 8, return_statement; 9, comment:"""Return all model output filenames inside a model output directory,
      sorted by iteration number.
  
      Parameters
      ----------
      dirname: str
          A path to a directory.
  
      Returns
      -------
      filenames: list[str]
          Paths to all output files inside `dirname`, sorted in order of
          increasing iteration number.
      """; 10, assignment; 11, call; 12, identifier:filenames; 13, call; 14, identifier:sorted; 15, argument_list; 16, attribute; 17, argument_list; 18, identifier:filenames; 19, keyword_argument; 20, identifier:glob; 21, identifier:glob; 22, call; 23, identifier:key; 24, identifier:_f_to_i; 25, attribute; 26, argument_list; 27, string; 28, identifier:format; 29, identifier:dirname; 30, string_content:{}/*.pkl
code: def get_filenames(dirname):
      """Return all model output filenames inside a model output directory,
      sorted by iteration number.
  
      Parameters
      ----------
      dirname: str
          A path to a directory.
  
      Returns
      -------
      filenames: list[str]
          Paths to all output files inside `dirname`, sorted in order of
          increasing iteration number.
      """
      filenames = glob.glob('{}/*.pkl'.format(dirname))
      return sorted(filenames, key=_f_to_i)