This is an example Flask | Python | Psycopg2 | PostgreSQL application that connects to the 7dbs database from Chapter 2 of Seven Databases in Seven Weeks Second Edition by Luc Perkins with Eric Redmond and Jim R. Wilson. The CSC 315 VM is assumed.

You must perform this one-time installation in the CSC 315 VM:

# install python pip and psycopg2 packages
sudo pacman -Syu
sudo pacman -S python-pip python-psycopg2 python-flask

To run the Flask application, simply execute:

export FLASK_APP=app.py
flask run
# then browse to http://127.0.0.1:5000/

Flask documentation:
https://flask.palletsprojects.com/

Psycopg2 documentation:
https://www.psycopg.org/

This example code is derived from:
https://www.postgresqltutorial.com/postgresql-python/
https://scoutapm.com/blog/python-flask-tutorial-getting-started-with-flask
https://www.geeksforgeeks.org/python-using-for-loop-in-flask/