My comment on that guide is that it expects everyone to run the latest version of Python. Last time I made a package following it, it turned out to be unusable in practice. I had to go back to setup.py and hunt down old guides and copy-paste parts from known-good packages to get something that was working for everyone involved. I'm not even talking about Python 2 (which can still be found in the wild). Something like Python 3.5 is still very common out there