def get_parent_objectives(self, objective_id=None):
if objective_id is None:<EOL><INDENT>raise NullArgument()<EOL><DEDENT>url_path = construct_url('<STR_LIT>',<EOL>bank_id=self._catalog_idstr,<EOL>obj_id=objective_id)<EOL>return objects.ObjectiveList(self._get_request(url_path))<EOL>
Gets the parents of the given objective.

        arg:    objective_id (osid.id.Id): the Id of an objective
        return: (osid.learning.ObjectiveList) - the parents of the
                objective
        raise:  NotFound - objective_id is not found
        raise:  NullArgument - objective_id is null
        raise:  OperationFailed - unable to complete request
        raise:  PermissionDenied - authorization failure
        compliance: mandatory - This method must be implemented.