code: public function valid()
      {
  
          if (strlen($this->container['uri']) > 500) {
              return false;
          }
          if (strlen($this->container['number']) > 120) {
              return false;
          }
          if (strlen($this->container['carrier']) > 120) {
              return false;
          }
          return true;
      }
docs: validate all the properties in the model
  return true if all passed
  
  @return bool True if all properties are valid