Could not make it work with self-hosted MacOs about setup-python

[konradpabjan]

If you're using a self-hosted runner, you need to setup the tools cache yourself. You can find instructions here: https://github.com/actions/setup-python#using-setup-python-with-a-self-hosted-runner

If you only need one version of Python, you can avoid using setup-python and whatever version of Python you have in PATH will be used.

Why is setup needed? Hosted runners that we maintain have multiple python versions cached and installed when the images get built. You can read up about it here: https://github.com/actions/setup-python#hosted-tool-cache

Essentially, if you're using one of our hosted runners, all that setup-python is doing is changing the PATH variable to point to a version of Python that is already installed. If you're using a self-hosted runner, you have to download and setup the necessary versions of Python first yourself.