@abc.abstractmethod<EOL><INDENT>def changed_values(self, notification_id, value_ids):<DEDENT>
pass<EOL>
The callback for notification of changed values.

        :param notification_id: the notification ``Id``
        :type notification_id: ``osid.id.Id``
        :param value_ids: the ``Ids`` of the ``Values``
        :type value_ids: ``osid.id.IdList``


        *compliance: mandatory -- This method must be implemented.*