code: def _check_base_classes(base_classes, check_for_type):
      
      return_value = False
      for base in base_classes:
          if base.__name__ == check_for_type:
              return_value = True
              break
          else:
              return_value = _check_base_classes(base.__bases__, check_for_type)
              if return_value is True:
                  break
  
      return return_value
docs: Indicate whether ``check_for_type`` exists in ``base_classes``.