def get_assessment_part_notification_session(self, assessment_part_receiver=None, proxy=None):
if proxy is None:<EOL><INDENT>raise NullArgument()<EOL><DEDENT>raise Unimplemented()<EOL>
Gets the ``OsidSession`` associated with the assessment part notification service.

        arg:    assessment_part_receiver
                (osid.assessment.authoring.AssessmentPartReceiver): the
                notification callback
        arg:    proxy (osid.proxy.Proxy): a proxy
        return:
                (osid.assessment.authoring.AssessmentPartNotificationSes
                sion) - an ``AssessmentPartNotificationSession``
        raise:  NullArgument - ``assessment_part_receiver`` or ``proxy``
                is ``null``
        raise:  OperationFailed - unable to complete request
        raise:  Unimplemented -
                ``supports_assessment_part_notification()`` is ``false``
        *compliance: optional -- This method must be implemented if
        ``supports_assessment_part_notification()`` is ``true``.*