A third option is to get them a very old Macbook -- they used to call MacOS "shiny BSD" for a reason, and if all you need is scratch and python, you can plug in some Ethernet and use brew to get whatever you want.
I would advise against this, because old Mac hardware does not support modern macOS and I'm about 99.9% certain brew will not run on anything other than the latest macOS (by their design). You may have some success just using their Formulae to compile everything you want from source, but at that point, I think things have become "a project" versus the shiny BSD approach
An alternative perspective is that having an old Mac is fine minus the "plug in some Ethernet," since the Internet is the biggest attack vector in that discussion
When I said old I meant old in apple fanboy terms, like, four years old but thanks for this caveat, you're right that if you go too far back you can't run macOS
(And honestly you probably will want to get a few packages etc so "no internet is a feature" is a little simplistic but I like the spirit of the thinking)
Comments
I would advise against this, because old Mac hardware does not support modern macOS and I'm about 99.9% certain brew will not run on anything other than the latest macOS (by their design). You may have some success just using their Formulae to compile everything you want from source, but at that point, I think things have become "a project" versus the shiny BSD approach
An alternative perspective is that having an old Mac is fine minus the "plug in some Ethernet," since the Internet is the biggest attack vector in that discussion
When I said old I meant old in apple fanboy terms, like, four years old but thanks for this caveat, you're right that if you go too far back you can't run macOS
(And honestly you probably will want to get a few packages etc so "no internet is a feature" is a little simplistic but I like the spirit of the thinking)