@utilities.arguments_not_none<EOL><INDENT>def acknowledge_item_notification(self, notification_id):<DEDENT>
raise errors.Unimplemented()<EOL>
Acknowledge an item notification.

        arg:    notification_id (osid.id.Id): the ``Id`` of the
                notification
        raise:  OperationFailed - unable to complete request
        raise:  PermissionDenied - authorization failure
        *compliance: mandatory -- This method must be implemented.*