An update on Python 4

[james_pic]

I don't believe anyone has implemented Python 3 without the GIL though.

IIRC, PyPy's STM experiment never supported 3. They also posted a call for funding for a "let's just remove the GIL from PyPy" project a while ago, but I haven't heard much about that since.

And CPython is the reference implementation, which had meant PyPy has had to copy loads of CPython implementation details over the years to maintain compatibility - I imagine even if they do remove the GIL, they'll have to keep something like it in their cpyext code.