/**
* Validates CSRF and returns the access token.
*
* @param string $code
* @param string $grant
*
* @return AccessToken
*
* @see League\OAuth2\Client\Provider\AbstractProvider::getAccessToken()
*/
public function getAccessToken($code, $grant = 'authorization_code')
{
$this->validateCsrf();
return $this->provider->getAccessToken($grant, ['code' => $code]);
}