/**
  * Get contact that belong to a specific list
  * @param string $accessToken - Constant Contact OAuth2 access token
  * @param mixed $list - Id of the list or a ContactList object
  * @param mixed $param - denotes the number of results per set, limited to 50, or a next parameter provided
  * from a previous getContactsFromList call
  * @return ResultSet
  * @throws IllegalArgumentException - if a ContactList object or id is not passed
  */
 public function getContactsFromList($accessToken, $list, $param = null)
 {
     $listId = $this->getArgumentId($list, 'ContactList');
     $param = $this->determineParam($param);
     return $this->listService->getContactsFromList($accessToken, $listId, $param);
 }