src/Http/Client/Guzzle/RequestBuilder.php
protected function buildForVersionFourOrFive(RequestInterface $request)
    {
        if (method_exists($this->guzzleClient, 'createRequest')) {
            $this->guzzleReCaptchaClient->setVersion(Version::VERSION_FOUR_FIVE);
            return $this->guzzleClient->createRequest(
                $request->getMethod(),
                (string)$request->getUri(),
                array (
                    'headers' => $request->getHeaders(),
                    'body' => $request->getBody()->getContents(),
                )
            );
        }

        return null;
    }
protected function buildForVersionFourOrFive(RequestInterface $request)
    {
        if (method_exists($this->guzzleClient, 'createRequest')) {
            $this->guzzleReCaptchaClient->setVersion(Version::VERSION_FOUR_FIVE);
            return $this->guzzleClient->createRequest(
                $request->getMethod(),
                (string)$request->getUri(),
                array (
                    'headers' => $request->getHeaders(),
                    'body' => $request->getBody()->getContents(),
                )
            );
        }

        return null;
    }
Build request object for Guzzle 4.* or 5.*

@param RequestInterface $request
@return mixed