static L<WithURL<S>> youTubeSearch(S query, double cacheExpirationDays default 1) {
  ret youTubeSearch(null, query, cacheExpirationDays);
}

static L<WithURL<S>> youTubeSearch(Playwright playwright, S query, double cacheExpirationDays default 1) {
  temp var myPlaywright = playwright != null ? null : tempPlaywright();
  var playwrightToUse = or(playwright, myPlaywright);
  
  ret youTubeSearch(playwrightToUse, query);
  // simplify query
  query = simpleSpacesAndTrim(lower(query));
  
  FileBasedStringMap cache = new(javaxCachesDir("YouTube Searches"));
  File f = cache.fileForKey(query);
  if (exists(f) && fileAgeInDays(f) < cacheExpirationDays)
    ret (L) unstructure(cache.get(query));
  
  var result = youTubeSearch_uncached(playwrightToUse, query);
  cache.put(query, indentedStructure(result));
  ret result;
}