/**
  * Do authentication with Google servers and store refresh_token
  *
  * @param $authorization_code
  *
  * @return bool
  */
 public function authenticate($authorization_code)
 {
     // Create a client object
     $client = new WPSEO_GWT_Google_Client();
     // Authenticate client
     try {
         $client->authenticate($authorization_code);
         // Get access response
         $response = $client->getAccessToken();
         // Check if there is a response body
         if ('' != $response) {
             $response = json_decode($response);
             if (is_object($response)) {
                 // Save the refresh token
                 $client->save_refresh_token($response->refresh_token);
                 return true;
             }
         }
     } catch (Google_AuthException $exception) {
     }
     return false;
 }