/**
  * Public function that does a POST to the Lists collection, passing a list object
  *
  * @param object $list - a valid list object with all required fields
  * @return string $code - returns success or fail code from API server
  */
 public function createList($list)
 {
     $utility = new CTCTUtility();
     $call = $utility->getApiPath() . '/ws/customers/' . $utility->getLogin() . '/lists';
     $listStruct = $this->createListXml(null, $list);
     $return = $utility->httpPost($call, $listStruct);
     $code = $return['info']['http_code'];
     return $code;
 }