@abc.abstractmethod<EOL><INDENT>def register_for_changed_qualifier(self, qualifier_id):<DEDENT>
pass<EOL>
Registers for notification of an updated qualifier.

        ``QualifierReceiver.changedQualifiers()`` is invoked when the
        specified qualifier is changed.

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

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