gof-design-patterns.md

https://sbcode.net/python/observer/#observerobserver_conceptpy

Python Finate State Machine + State Pattern: https://auth0.com/blog/state-pattern-in-python/

Dependency Injection in Python https://towardsdev.com/dependency-injection-in-python-c4248a096800

Observer Pattern

Observer Pattern

Observer Pattern Vs. Publisher-Subscriber

Observer Pattern Vs Pub-Sub Pattern