Django IIS deployment with HttpPlatformHandler

I’m trying to deploy my Django app to IIS but the page is just infinitely loading without any error messages. It’s weird. Here’s my web.config:

<?xml version="1.0" encoding="utf-8"?>
      <add name="PythonHandler" path="*" verb="*" modules="httpPlatformHandler" resourceType="Unspecified"/>
    <httpPlatform processPath="c:\inetpub\wwwroot\one-two-api\venv\Scripts\python.exe"
                  arguments="c:\inetpub\wwwroot\one-two-api\ runserver"
        <environmentVariable name="SERVER_PORT" value="%HTTP_PLATFORM_PORT%" />

The error took a while to come up but it was a 502.3 bad gateway with an error code of 0x8007042b.

I was able to setup a Django Website in deployment environment Windows Server IIS following this instruction: Django On IIS.

But it uses python runserver, where runserver is a lightweight web server for usage on a local development machine only. runserver doc says: do not use this server in a production setting.