code: public function addHeaders($request, $url)
      {
          if ($url->getUsername() && $url->getPassword()) {
              $username = $url->getUsername();
              $password = $url->getPassword();
          } elseif ($realm = $this->findRealmFromUrl($url)) {
              $username = $realm->getUsername();
              $password = $realm->getPassword();
          } else {
              return;
          }
          $this->addBasicHeaders($request, $username, $password);
      }
docs: Presents the appropriate headers for this location.
  
  @param SimpleHttpRequest $request  Request to modify.
  @param SimpleUrl $url              Base of realm.