I have built a chat app in a few different ways.
Initially I set out to build a simple command line chat app with python, to get a better understanding of sockets, but it ended up being a good opportunity to learn about a lot more, and test my skills.
It led to me getting to grips with basic encryption (asymmetric and symmetric keys) and ORMs (had only used raw SQL queries with pg-promise/psycopg2 before now), among other things.
Uses the built in socket library, as well as the RSA and cryptography packages for encryption.
Server - simply run python3 server.py. This will allow local connections to port 8004 currently Client - run python3 client.py, enter a username, and start chatting.