[Python-Dev] Another update for PEP 394 -- The "python" Command on Unix-Like Systems

[Antoine Pitrou]

On Wed, 13 Feb 2019 16:24:48 +0100
Petr Viktorin <encukou at gmail.com> wrote:
> PEP 394 says:
> 
>  > This recommendation will be periodically reviewed over the next few
>  > years, and updated when the core development team judges it
>  > appropriate. As a point of reference, regular maintenance releases
>  > for the Python 2.7 series will continue until at least 2020.  
> 
> I think it's time for another review.
> I'm especially worried about the implication of these:
> 
> - If the `python` command is installed, it should invoke the same
>    version of Python as the `python2` command
> - scripts that are deliberately written to be source compatible
>    with both Python 2.x and 3.x [...] may continue to use `python` on
>    their shebang line.
> 
> So, to support scripts that adhere to the recommendation, Python 2
> needs to be installed :(

I think PEP 394 should acknowledge that there are now years of
established usage of `python` as Python 3 for many conda users.

Regards

Antoine.