public function requestToken(TokenRequest $request)
    {
        $result = $this->request('POST', '/tokens', [
            'card[number]' => $request->getCardNumber(),
            'card[exp_month]' => $request->getExpirationMonth(),
            'card[exp_year]' => $request->getExpirationYear(),
            'card[cvc]' => $request->getSecurityCode(),
            'card[name]' => $request->getHolderName(),
            'currency' => $request->getCurrency(),
            'email' => $request->getEmail(),
        ]);

        return $this->objectConverter->convert($result);
    }