public function create($group_id = null)
 {
     $group = self::load_group($group_id);
     if ($this->post) {
         $event = Event::find_by_id($_POST['event']);
         if (!$event) {
             Site::Flash("error", "Unable to find the event you selected");
             Redirect("admin/groups/{$group->id}");
         }
         $event_group = new EventGroup();
         $event_group->event_id = $_POST['event'];
         $event_group->group_id = $group->id;
         if ($event_group->save()) {
             Site::Flash("{$event->name} has been added to this group");
         } else {
             Site::Flash("error", "Unable to add {$event->name} to this group");
         }
         Redirect("admin/groups/{$group->id}");
     }
     Redirect("admin/groups/{$group->id}");
 }