code: public function getAccessToken($settings,
                                      OAuthConsumerInterface $consumer,
                                      OAuthTokenInterface $token)
      {
          $url = $settings['auth_api_url'].$settings['access_token_uri'];
          $params = ['oauth_verifier' => $token->verifier];
          $options = [
                  'Content-Type: application/x-www-form-urlencoded',
                  'Content-Length: '.strlen(http_build_query($params)),
          ];
  
          $headers = $this->headers($settings, 'POST', $url, $consumer, $token, $options);
  
          // build request
          $request = compact('url', 'headers', 'params');
  
          return $this->token->makeAccessToken($this->http->post($request));
      }
docs: Transforms a verifier (request) token
  into an access token.
  
  @param array                                                                  $settings
  @param Vinelab\Auth\Social\Providers\Twitter\Contracts\OAuthConsumerInterface $consumer
  @param Vinelab\Auth\Social\Providers\Twitter\Contracts\OAuthTokenInterface    $token
  
  @return Vinelab\Auth\Social\Providers\Twitter\Contracts\OAuthTokenInterface