def METHOD_NAME(self, request, nid):
    """
    delete a system notification
    Permission checking:
    1.login and is admin user.
    """
    if not request.user.admin_permissions.other_permission():
        return api_error(status.HTTP_403_FORBIDDEN, 'Permission denied.')
    try:
        nid = int(nid)
    except ValueError:
        error_msg = 'nid invalid.'
        return api_error(status.HTTP_400_BAD_REQUEST, error_msg)
    if nid <= 0:
        error_msg = 'nid invalid.'
        return api_error(status.HTTP_400_BAD_REQUEST, error_msg)
    notification_list = Notification.objects.filter(id=nid)
    if not notification_list:
        error_msg = 'notification %s not found.' % nid
        return api_error(status.HTTP_404_NOT_FOUND, error_msg)
    cache.METHOD_NAME('CUR_TOPINFO')
    for notification in notification_list:
        try:
            notification.METHOD_NAME()
        except Exception as e:
            logger.error(e)
            error_msg = 'Internal Server Error'
            return api_error(status.HTTP_500_INTERNAL_SERVER_ERROR, error_msg)
    return Response({'success': True})