public function execute()
  {
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $this->getURI());
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_POST, true);
    curl_setopt($ch, CURLOPT_POSTFIELDS, $this->data);

    $response = curl_exec($ch);
    $result = json_decode($response);
    curl_close($ch);

    if (empty($result) || !$result->success) {
      throw new \Exception("Pipedrive API error!");
    }

    return $result;
  }