code: def return_type(self, return_type):
          
  
          return_type = _ensure_unicode(return_type)
  
          # We perform this check after the initialization to avoid errors
          # in test tools that show the object with repr().
          if return_type not in ALL_CIMTYPES:
              raise ValueError(
                  _format("Invalid CIM type: {0}", return_type))
          if return_type == 'reference':
              raise ValueError("Method cannot have a reference return type")
  
          # pylint: disable=attribute-defined-outside-init
          self._return_type = return_type
docs: Setter method; for a description see the getter method.