private function getRetryOptions(array $options)
    {
        return [
            'retries' => isset($options['retries'])
                ? $options['retries']
                : $this->retries,
            'retryFunction' => isset($options['restRetryFunction'])
                ? $options['restRetryFunction']
                : $this->retryFunction,
            'delayFunction' => isset($options['restDelayFunction'])
                ? $options['restDelayFunction']
                : $this->delayFunction,
            'calcDelayFunction' => isset($options['restCalcDelayFunction'])
                ? $options['restCalcDelayFunction']
                : $this->calcDelayFunction
        ];
    }