[$] Cooperative package management for Python

A longstanding tug-of-war between system package managers and Python's owninstallation mechanisms (primarily pip, but there are others) lookson its way to being resolved-or at least regularized. PEP 668("Graceful cooperation between external and Python packagemanagers") has been created to provide ways for the two types of package installationtowork together, rather than at cross-purposes at times.Since many operating systems depend on Python tools, with package versionsthat may differ from those of users' Python applications, making them play togethernicely should result in more stable systems.