public function isTimeZoneValid($timeZone)
 {
     $stat = $this->siteContainer['databasehelper']->getPDO()->prepare("SELECT country.* FROM country ");
     $stat->execute();
     while ($data = $stat->fetch(\PDO::FETCH_ASSOC)) {
         $country = new CountryModel();
         $country->setFromDataBaseRow($data);
         if ($country->hasTimeZone($timeZone)) {
             return true;
         }
     }
     return false;
 }