[python-committers] Python 4.0 or Python 3.10?

[Yury Selivanov]

On Tue, Sep 25, 2018 at 6:33 PM Victor Stinner <vstinner at redhat.com> wrote:
>
> Hi,
>
> I would prefer to never ever break the backward compatibility in Python. To make it clear I suggest to use 4.0 for the release following Python 3.7.

I think Serhiy made a strong argument that the code like below would
break if we release Python 4.0:

     PY3 = sys.version_info[0] == 3
     if not PY3:
         ... # implies Python 2

I think we all have seen code like that; it's a common pattern.  So by
just bumping the version to 4.0 you would break the compatibility for
some libraries and frameworks.  And maybe breaking it is fine if
there's a very strong technical reason, but doing that just to make a
statement isn't worth it, IMHO.

Yury