public ActionResult _DeleteGroupUser(string group_id, string user_id)
        {
            GroupUserDTO groupUserDTO = new GroupUserDTO();

            groupUserDTO.id_group = group_id;
            groupUserDTO.user_id  = user_id;
            if (groupProvider.deleteGroupUser(groupUserDTO).Result)
            {
                return(new HttpStatusCodeResult(200));
            }
            return(new HttpStatusCodeResult(404, "Can't find that"));
        }