// page contents is cached using webScrape
// returns pairs (video id, title plus stats)
static LPairS videoLinksFromYouTubePage(S url, O... _) {
  S html = emitIntermediate html(_, webScrape(youtubeURL(url)));
  LS l = regexpExtractAll([[\\"(label|videoId)\\":\\"(.*?)\\"]], html);
  //print(+l);
  S videoId = null;
  new LPairS out;
  for (S s : l) {
    PairS p = listToPair(unquoteAll(splitAtColon(unquoteRaw(s)))), continue if null;
    if (eq(p.a, "videoId")) videoId = p.b;
    else out.add(pair(videoId, p.b));
  }
  ret out;
}