public function text_datetime_timestamp_timezone($value)
 {
     $test = is_array($value) ? array_filter($value) : '';
     if (empty($test)) {
         return '';
     }
     $tzstring = null;
     if (is_array($value) && array_key_exists('timezone', $value)) {
         $tzstring = $value['timezone'];
     }
     if (empty($tzstring)) {
         $tzstring = rrze_Meta_Box::timezone_string();
     }
     $offset = rrze_Meta_Box::timezone_offset($tzstring, true);
     if (substr($tzstring, 0, 3) === 'UTC') {
         $tzstring = timezone_name_from_abbr('', $offset, 0);
     }
     $value = new DateTime($value['date'] . ' ' . $value['time'], new DateTimeZone($tzstring));
     $value = serialize($value);
     return $value;
 }
 public function field_timezone_offset()
 {
     return rrze_Meta_Box::timezone_offset($this->field_timezone());
 }