public function deleteBackup($backupId, $callbackUrl, $callbackMethod, $callerData)
    {
        if ($this->connector->getURL() === null) {
            return 'Cannot find site URL from configuration.';
        }
        $url = $this->connector->getURL().self::VERSION.$this->connector->getSiteID().'/backups/'.$backupId;
        $params = [
            'callback_url' => $callbackUrl,
            'callback_method' => $callbackMethod,
            'callerData' => $callerData,
        ];

        $response = $this->connector->connecting($url, $params, 'DELETE');

        // @codingStandardsIgnoreStart
        if (isset($response->task_id)) {
            return $response->task_id;
            // @codingStandardsIgnoreEnd
        }

        return $response;
    }