code: def char_num_transformer(input_item):
      """
      Transform the input string to a proper key for char-num sorting.
  
      :param input_item: input item
      :type input_item: str
      :return: key as tuple
      """
      return [
          (input_item, False, False)
          if not re.findall(r"\d+", input_item)
          else (
              input_item[: re.search(r"\d+", input_item).start()],
              int(re.findall(r"\d+", input_item)[0]),
              input_item[re.search(r"\d+", input_item).end() :],
          )
      ]
  
imports: from __future__ import division
  import sys
  import math
  import numpy
  import re
  from .pycm_param import *
  from .pycm_error import pycmMatrixError
  from warnings import warn
  from functools import wraps
label_desc: Use image node_id 32 for calling a global function with example usage: char_num_transformer(input_item) and returns: list