Add Virtual Threads to Python

[EpicWink (Laurie O)]

@jamestwebber

Python running in a virtual thread can use extensions, but potentially there is some issue with that code calling back in Python. I’m not sure what an example of such a usage might be,

An example:

from scipy.optimize import minimize

def square(x):
    return x**2

xmin = minimize(square, x0=0.5)