static File playRandomSoundFromFreesoundOrg(S query) {
  print("Freesound search: " + query);
  S url = "https://freesound.org/search/?q=" + urlencode(query);
  S html = loadPage(url);
  L<S> tok = htmlTok(html);
  LL<S> tags = findContainerTagWithParams(tok, 'a, class := 'mp3_file);
  L<S> tag = random(tags);
  if (tag == null) null;
  L<S> duration = first(findContainerTagWithParams(
    subList(tok, indexOfSubList(tok, tag)-1), 'span,  class := 'duration));
  printStruct(+duration);
  S mp3 = "https://freesound.org" + getTagParam(second(tag), "href");
  File mp3File = programFile(urlencode(mp3));
  if (fileLength(mp3File) == 0)
    loadBinaryPageToFile(mp3, mp3File);
  playMP3(mp3File);
  ret mp3File;
}