docs: public Iterable<BoxItem.Info> getChildren(final String... fields) {
          return new Iterable<BoxItem.Info>() {
              @Override
              public Iterator<BoxItem.Info> iterator() {
                  String queryString = new QueryStringBuilder().appendParam("fields", fields).toString();
                  URL url = GET_ITEMS_URL.buildWithQuery(getAPI().getBaseURL(), queryString, getID());
                  return new BoxItemIterator(getAPI(), url);
              }
          };
      }