code: def _compare_lists(list1, list2, custom_cmp):
      
      if len(list1) != len(list2):
          return False
      for element1, element2 in zip(list1, list2):
          if not custom_cmp(element1, element2):
              return False
      return True
docs: Compare twolists using given comparing function.
  
      :param list1: first list to compare
      :param list2: second list to compare
      :param custom_cmp: a function taking two arguments (element of
          list 1, element of list 2) and
      :return: True or False depending if the values are the same