public function getActivityClassificationsAttribute()
 {
     $activityClassification = ActivityClassification::find($this->activity_classification_id);
     if ($activityClassification == null) {
         return '';
     }
     return $activityClassification->toArray();
 }
 public function delete($id)
 {
     ActivityClassification::find($id)->delete();
     $ret['meta']['code'] = 1;
     echo json_encode($ret);
 }