I don’t mind numpy becoming a core Python library in 4.0. There are plenty of core libraries like heapq that I never use. It’s a bit awkward coding a tensor as a list of lists when you’re writing code that might be run by someone who doesn’t have numpy installed but it’s no big deal if numpy isn’t included.

Though one advantage of not including numpy with Python is that the devs are free to release updates anytime rather than waiting for the next Python release.