public function request($endPoint, $httpVerb = 'GET', $data = array())
    {
        // Validate API
        if (!$this->apiKey) {
            throw new \Exception('MailChimp API Key must be set before making request!');
        }
        
        $endPoint = ltrim($endPoint, '/');
        $httpVerb = strtoupper($httpVerb);
        $requestUrl = $this->apiUrl.$endPoint;
        
        return $this->curlRequest($requestUrl, $httpVerb, $data);
    }