@utilities.arguments_not_none<EOL><INDENT>def get_gradebook_ids_by_grade_system(self, grade_system_id):<DEDENT>
<EOL>mgr = self._get_provider_manager('<STR_LIT>', local=True)<EOL>lookup_session = mgr.get_grade_system_lookup_session(proxy=self._proxy)<EOL>lookup_session.use_federated_gradebook_view()<EOL>grade_system = lookup_session.get_grade_system(grade_system_id)<EOL>id_list = []<EOL>for idstr in grade_system._my_map['<STR_LIT>']:<EOL><INDENT>id_list.append(Id(idstr))<EOL><DEDENT>return IdList(id_list)<EOL>
Gets the list of ``Gradebook``  ``Ids`` mapped to a ``GradeSystem``.

        arg:    grade_system_id (osid.id.Id): ``Id`` of a
                ``GradeSystem``
        return: (osid.id.IdList) - list of gradebook ``Ids``
        raise:  NotFound - ``grade_system_id`` is not found
        raise:  NullArgument - ``grade_system_id`` is ``null``
        raise:  OperationFailed - unable to complete request
        raise:  PermissionDenied - authorization failure
        *compliance: mandatory -- This method must be implemented.*