How to make gunicorn timeout with a simple app?

app.py

import requests
from flask import Flask
app = Flask(__name__)
app.debug=True

@app.route("/hello")
def world():
    return "Hello world"

@app.route("/")
def hello():
    return requests.get('http://127.0.0.1:8000/hello').text

if __name__ == "__main__":
    app.run(debug=True)

scripts.sh

gunicorn --debug app:app