private function _createRefund(array $response)
    {
        $model = new Refund();
        $model->setId($response['id']);
        $model->setAmount($response['amount']);
        $model->setStatus($response['status']);
        $model->setDescription($response['description']);
        $model->setLivemode($response['livemode']);
        $model->setCreatedAt($response['created_at']);
        $model->setUpdatedAt($response['updated_at']);
        $model->setResponseCode($response['response_code']);
        //Refund doesn't have the array index 'transaction' when using getOne
        $model->setTransaction(isset($response['transaction']) ? $this->_convertResponseToModel($response['transaction'], 'transaction') : null);
        $model->setAppId($response['app_id']);
        return $model;
    }