code: public function tryGetFirst($name, &$value): bool
      {
          try {
              $value = $this->get($name)[0];
  
              return true;
          } catch (OutOfBoundsException $ex) {
              return false;
          }
      }
docs: Tries to get the first value of a header
  
  @param mixed $name The name of the header whose value we want
  @param mixed $value The value, if it is found
  @return bool True if the key exists, otherwise false
  @throws RuntimeException Thrown if the key could not be calculated