On 17 December 2016 at 20:15, Marc-Andre Lemburg <report@bugs.python.org>
wrote:

> Another use case to consider is embedding the Python
> interpreter in another application. In such situations,
> the C locale will usually already be set by the main
> application and it may conflict with the LANG or other
> locale env var settings, since the user may have chosen
> to use a different locale in the context of the application.
>

Aye, that's the origin of the split proposal to only emit a warning in the
shared library (since CPython might only be a piece of a larger
application), but implement actual locale coercion (by overriding LANG and
LC_ALL in the process environment) in the command line app's main()
function (as in that case we know CPython *is* the application).

The hard part of writing the PEP isn't really going to be explaining the
proposal itself (I expect it to be around a 20 line patch to the C code) -
it's going to be explaining why all the other possibilities we've
considered over the years don't work, and why we (as in the Fedora Python
SIG) think this one actually stands a chance of working properly :)