code: public function get($name)
      {
          if (!array_key_exists($name, $this->data)) {
              throw new \InvalidArgumentException(sprintf(
                  'The value for "%s" does not exists.',
                  $name
              ));
          }
  
          return $this->data[$name];
      }
docs: Get
  
  @param string $name  name of parameter
  
  @return string   metadata value