code: public T photos_getTags(Collection<Long> photoIds)
      throws FacebookException, IOException {
      return this.callMethod(FacebookMethod.PHOTOS_GET_TAGS,
                             new Pair<String, CharSequence>("pids", delimit(photoIds)));
    }
docs: Retrieves the tags for the given set of photos.
  @param photoIds The list of photos from which to extract photo tags.
  @return the created album