This regards https://github.com/raspberrypi/documentation/blob/master/linux/software/python.md

Helpful page. I've not used pip yet, preferring apt-get if at all possible as suggested (and have been able thus far to use only "stock" Python). All my Pi's are running the Stretch Lite version, save one which is Jessie Desktop, and it looks to me as though the desktop version may be the only one which includes pip? The page hasn't been updated recently and only mentions Wheezy and Jessie. I'd guess the pattern continues with Stretch (and maybe Buster). Could one just say that the Lite versions do not include pip?

Cheers, and Thanks,
Bob