The solution to Python packages is the 'pypi2nix' tool. This is an alternate approach that you see also used in the blog post, this time with vgo2nix. These tools take a set of dependencies (e.g. requirements.txt) and generate Nix expressions to build all of them from source.
Guix has `guix import pypi PACKAGE`, which spits out a complete definition that you can pop into a file or the main Guix repository.
'guix import' also takes a --recursive argument, which makes it recursively consider any dependencies and produce package definitions for those not already available.
