docs: def get_asset_notification_session(self, asset_receiver):
          """Gets the notification session for notifications pertaining to asset changes.
  
          arg:    asset_receiver (osid.repository.AssetReceiver): the
                  notification callback
          return: (osid.repository.AssetNotificationSession) - an
                  ``AssetNotificationSession``
          raise:  NullArgument - ``asset_receiver`` is ``null``
          raise:  OperationFailed - unable to complete request
          raise:  Unimplemented - ``supports_asset_notification()`` is
                  ``false``
          *compliance: optional -- This method must be implemented if
          ``supports_asset_notification()`` is ``true``.*
  
          """
          if not self.supports_asset_notification():
              raise errors.Unimplemented()
          # pylint: disable=no-member
          return sessions.AssetNotificationSession(runtime=self._runtime, receiver=asset_receiver)