This is a minimail containerized Flask app using Python 3.8 and Redis to as database.
$ docker-compose up --build
After build success, the web will be running on http://0.0.0.0:5000/ , if everything runs as expected you can see "Hello World! I have been seen {n} times." (you will see the times you hit refresh, it expires after 60 sec.)
$ docker exec -ti py_redis_app flask shell