code: public ListenableFuture<ResourceSet<T>> readAsync(final TwilioRestClient client) {
          return Twilio.getExecutorService().submit(new Callable<ResourceSet<T>>() {
              public ResourceSet<T> call() {
                  return read(client);
              }
          });
      }
docs: Execute an async request using specified client.
  
  @param client client used to make request
  @return future that resolves to the ResourceSet of objects