code: public CreateStreamResponse createStream(String playDomain, String app, String pushStream) {
          CreateStreamRequest request = new CreateStreamRequest();
          request.withPlayDomain(playDomain)
                  .withApp(app)
                  .withPublish(new CreateStreamRequest.PublishInfo().withPushStream(pushStream));
          return createStream(request);
      }
docs: Create a domain stream in the live stream service.
  
  @param playDomain The domain which this stream belongs to
  @param app The app which this stream belongs to, may not exist when create stream
  @param pushStream, name of this stream
  @return the response