you shouldn't import a specific python version please look at https://github.com/NixOS/nixpkgs/blob/master/doc/languages-frameworks/python.section.md#handling-dependencies

Before trying to handle Python 2 vs 3, I received the error: google-api-core-1.22.1 not supported for interpreter python2.7. I'm reasonably confident this comes from...

... transitively due to google_api_python_client.

I was unable to get incantations of disabled = ! isPy3k or disabled = isPy27 to work... builds still gave me a Python 2 interpreter error. I ended up with a pattern that worked by cribbing from other PRs.

What am I missing?

@jonringer ... thoughts?

Using pythonXPackages isn't allowed from python-modules as this will mix interpreter versions for a given package. For example, if you were to do python37Packages.<mypkg>, but the expression pulled from python3[8]Packages. Python will be mis-importing several libraries, and this will likely cause issues at runtime.

Please refer to Python dependency handling on the best practices for handling dependencies within python-modules. Namely, you should be importing each python package individually, and not refer to another python package set (E.g. python3Packages).

If you're new to nixpkgs, you're free to view some of my videos on nixpkgs and python:

• Python packaging using nixpkgs
• Adding a package to nixpkgs unstable

convert it over to using the individual packages and have it build for python3, and we'll go from there :)

I picked this back up. I think I did all the needful in 0fbbe37022c6c14ee8ab325637f9a6df253f6d22