public override IProcessor <int?, int?> CreateIdentityProcessor(int bufferSize)
{
var materializer = ActorMaterializer.Create(System);
var identity = Flow.Create <int?>().Select(x => x).Named("identity").ToProcessor().Run(materializer);
var left = new VirtualProcessor <int?>();
var right = new VirtualProcessor <int?>();
left.Subscribe(identity);
identity.Subscribe(right);
return(ProcessorFromSubscriberAndPublisher(left, right));
}