@Override
 public int hashCode() {
   int result = url.hashCode();
   result = 31 * result + (media_url != null ? media_url.hashCode() : 0);
   result = 31 * result + (preview_url != null ? preview_url.hashCode() : 0);
   result = 31 * result + start;
   result = 31 * result + end;
   result = 31 * result + type;
   result = 31 * result + width;
   result = 31 * result + height;
   result = 31 * result + (video_info != null ? video_info.hashCode() : 0);
   result = 31 * result + (card != null ? card.hashCode() : 0);
   result = 31 * result + (page_url != null ? page_url.hashCode() : 0);
   return result;
 }