code: def ngrok_url():
      
      try:
          ngrok_resp = requests.get("http://localhost:4040/api/tunnels")
      except requests.ConnectionError:
          # I guess ngrok isn't running.
          return None
      ngrok_data = ngrok_resp.json()
      secure_urls = [
          tunnel["public_url"]
          for tunnel in ngrok_data["tunnels"]
          if tunnel["proto"] == "https"
      ]
      return secure_urls[0]
docs: If ngrok is running, it exposes an API on port 4040. We can use that
      to figure out what URL it has assigned, and suggest that to the user.
      https://ngrok.com/docs#list-tunnels