@abc.abstractmethod<EOL><INDENT>def get_assessment_offered_notification_session(self, assessment_offered_receiver):<DEDENT>
return<EOL>
Gets the notification session for notifications pertaining to offered assessment changes.

        :param assessment_offered_receiver: the assessment offered receiver interface
        :type assessment_offered_receiver: ``osid.assessment.AssessmentOfferedReceiver``
        :return: an ``AssessmentOfferedNotificationSession``
        :rtype: ``osid.assessment.AssessmentOfferedNotificationSession``
        :raise: ``NullArgument`` -- ``assessment_offered_receiver`` is ``null``
        :raise: ``OperationFailed`` -- unable to complete request
        :raise: ``Unimplemented`` -- ``supports_assessment_offered_notification()`` is ``false``

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