i have python web app build on top of BaseHTTPServer, which runs on specyfic port. It runs system commands and shows output. I want do limit access to this app. What are posible ways to do it? Requirements:

it must not be limited to LAN
simple to implement/deploy
Common methods: VPN access. Firewalls, logging, denyhosts style defences, complicated root passwords, no su, run as its own user.
(if it was my personal server)
Logic bombs
Secure python web app