@abc.abstractmethod<EOL><INDENT>def get_qualifier_notification_session(self, qualifier_receiver):<DEDENT>
return<EOL>
Gets the notification session for notifications pertaining to qualifier changes.

        :param qualifier_receiver: the qualifier receiver
        :type qualifier_receiver: ``osid.authorization.QualifierReceiver``
        :return: a ``QualifierNotificationSession``
        :rtype: ``osid.authorization.QualifierNotificationSession``
        :raise: ``NullArgument`` -- ``qualifier_receiver`` is ``null``
        :raise: ``OperationFailed`` -- unable to complete request
        :raise: ``Unimplemented`` -- ``supports_qualifier_notification()`` is ``false``

        *compliance: optional -- This method must be implemented if
        ``supports_qualifier_notification()`` is ``true``.*