Can't return status 101 for websocket

Developers Workers
1

This is the tutorial I am following: https://developers.cloudflare.com/workers/learning/using-websockets/

Part of the tutorial shows this code

  return new Response(null, {
    status: 101,
    webSocket: client,
  });

But when it runs it errors saying
Responses may only be constructed with status codes in the range 200 to 599, inclusive.

Is this a bug with cloudflare or am I missing something?