Edge case 1: interpreter constraint env markers. `Black`'s lockfile varies if it was generated w/ Py36 vs Py39, e.g. the

typing-extensions

dep Poetry handles this, and specifically based on what you set the

python

value to. If you set it to

==3.9

, the lockfile only works w/ 3.9. If you set to

>=3.7,<3.10

, it works with all those intepreters, even tho you only run it w/ one interpreter! Amazing