It's been in the works for a while.

There’s more than one way to thread (or not to thread) a Python program. We point you to several threading resources, a fast new static type checker from Astral, a monkey patch for Pandas that adds ...

It is obvious that global variable are always shared and in most cases this isn’t a problem. However, suppose you have some existing code that makes use of a global variable to store its state and we ...