protected static function is_valid_shipping_state($country, $state)
 {
     if ($country) {
         $has_states = fflcommerce_countries::country_has_states($country);
         if ($state && $has_states) {
             return fflcommerce_countries::country_has_state($country, $state);
         } else {
             if ($has_states) {
                 return false;
             }
         }
         return true;
     }
     return false;
 }