Coexistence of Python 2.x and 3.x on same OS

[Ian Kelly]

On Sat, Oct 6, 2012 at 1:27 AM,  <wxjmfauth at gmail.com> wrote:
> Using Python on Windows is a dream.
>
> Python uses and needs the system, but the system does
> not use Python.
>
> Every Python version is installed in its own isolated
> space, site-packages included and without any defined
> environment variable. Every Python can be seen as a
> different application.
> Knowing this, it is a no-problem to use the miscellaneous
> versions; can be with the console, with an editor, with
> .bat or .cmd files, with the Windows "start menu" launcher,
> ... like any application.
>
> The file extension is a double sword. Do not use it or
> unregister it, the msi installer allows to do this.
> It is the same task/problem as with any file, .txt, .png, ...
>
> The new Python launcher is a redondant tool.

Yes, because all scripts are only ever run by the person who wrote
them.  The main benefit here is for distribution of Python scripts
with version requirements.  Just because you can rely on your Python
installation to be in C:\Python27 doesn't mean you can rely on
somebody else's installation to be there, or on their file
associations to be configured for the correct version.