code: public String getPhotosFirstDate() {
      return (person == null || person.photos == null || person.photos.firstDate == null) ? null : person.photos.firstDate._content;
    }
docs: Get the unix timestamp of the first photo uploaded by the user.
  
  You can use {@link JinxUtils#parseTimestampToDate(String)} to convert this value to a Date object.
  
  @return unix timestamp of the first photo uploaded by the user, or null if the value was not returned.