static O youTubeGetChatMessages(S liveStreamID) {
  S url ="https://www.googleapis.com/youtube/v3/liveChat/messages?liveChatId=" + urlencode(liveStreamID) + "&part=id,snippet,authorDetails&key=" + youTubeDataAPIKey();
  O result = loadJSONPage(url);
  printStruct(result);
  ret result;
}