docker-compose up FileNotFoundError for arch/manjaro

[FatjonZOGAJ]

Wasted a bit of time as the error messages are quite archaic and only mention FileNotFound and package/connection errors. Figured I'd give a heads up for other students who use arch/manjaro:

Make sure to first start docker manually, as this is not done on manjaro by default:
sudo systemctl start docker

As mentioned here:
docker/compose#7896
https://stackoverflow.com/questions/64633015/problem-launching-docker-compose-python-modules-not-installed