code: def get_assessment_notification_session(self, assessment_receiver):
          
          if not self.supports_assessment_notification():
              raise errors.Unimplemented()
          # pylint: disable=no-member
          return sessions.ItemNotificationSession(runtime=self._runtime, receiver=assessment_receiver)
docs: Gets the notification session for notifications pertaining to assessment changes.
  
          arg:    assessment_receiver
                  (osid.assessment.AssessmentReceiver): the assessment
                  receiver interface
          return: (osid.assessment.AssessmentNotificationSession) - an
                  ``AssessmentNotificationSession``
          raise:  NullArgument - ``assessment_receiver`` is ``null``
          raise:  OperationFailed - unable to complete request
          raise:  Unimplemented - ``supports_assessment_notification()``
                  is ``false``
          *compliance: optional -- This method must be implemented if
          ``supports_assessment_notification()`` is ``true``.*