@abc.abstractmethod<EOL><INDENT>def register_for_deleted_grade_system(self, grade_system_id):<DEDENT>
pass<EOL>
Registers for notification of a deleted grade system.

        ``GradeSystemReceiver.deletedGradeSystems()`` is invoked when
        the specified system is removed from this gradebook.

        :param grade_system_id: the ``Id`` of the grade system to monitor
        :type grade_system_id: ``osid.id.Id``
        :raise: ``NullArgument`` -- ``grade_system_id is null``
        :raise: ``OperationFailed`` -- unable to complete request
        :raise: ``PermissionDenied`` -- authorization failure

        *compliance: mandatory -- This method must be implemented.*