public function setUpdatedToToday()
 {
     $song = new Song();
     $sortedPlaylist = $song->orderby('updated_at', 'asc')->get();
     $previousSongsDuration = 0;
     $now = Carbon::now('UTC')->addHours(2);
     foreach ($sortedPlaylist as $key => &$value) {
         $key = intval(json_encode($key));
         if ($key === 0) {
             $value->updated_at = $now;
         } else {
             $previousSongsDuration += $sortedPlaylist[$key - 1]->video_duration;
         }
         $nextUpdateAtStop = $now->timestamp + $previousSongsDuration;
         $value->updated_at = Carbon::createFromTimestamp($nextUpdateAtStop)->toDateTimeString();
         $value->save();
     }
     return \Response::json($sortedPlaylist);
 }