private function importMissionTrips()
 {
     $table = 'mission_trips';
     $items = $this->getMissionTrips();
     MissionTrip::unguard();
     DB::table($table)->truncate();
     foreach ($items as $item) {
         $location = MissionLocation::findBySlug($item->location_slug);
         $data = get_object_vars($item);
         unset($data['location_slug']);
         $model = new MissionTrip($data);
         $model->mission_location_id = is_null($location) ? null : $location->id;
         $model->save();
     }
 }