How to run Flask + socketio + gunicorn?

Question

Flask

Good afternoon. Tell me, please, one moment.
Simplified folder structure:

app/
   __init__.py
app.py

app.py

from app import app
from app import socketio

socketio.run(app, "127.0.0.1", 8000)

__init__.py

from flask import Flask
from flask_socketio import SocketIO

app = Flask(__name__)
app.config.from_object('config.Config')
async_mode = None
socketio = SocketIO(app, async_mode=async_mode,  logger=True, engineio_logger=True)

This is how it works : python app.py
This is not how it works : gunicorn --worker-class eventlet -w 5 app:socketio
How to run flask through gunicorn?