public function addReportPhoto($photo_id, $reason)
    {
        if (!is_numeric($photo_id) || 0 >= $photo_id) {
            throw new InvalidArgumentException(
                "Api::addReportPhoto photo_id field should be positive integer");
        }

        if (!is_string($reason) || 0 >= strlen($reason)) {
            throw new InvalidArgumentException("addReportPhoto reason field needs to be a non-empty string");
        }

        /** @var $command \Guzzle\Service\Command\AbstractCommand */
        $command = $this->client->getCommand('AddReportPhoto',array('id' => $photo_id, 'report'=>array('reason' => $reason)));
        return $this->executeCommand($command);
    }