bug#46569: python can't find internal pip modules in environment from manifest

[Maxim Cournoyer]

Hi Jelle,

Jelle Licht <jlicht@fsfe.org> writes:

> Python can not load all pip-related python modules when loaded from a
> manifest file, yet seems to work fine when loaded 'directly' as part of
> a `guix environment'-invocation.
>
>
> Provided that we have a file in `hi.py':
>
> import pip
> print("halfwaypoint")
> import pip._internal.index.package_finder
> print("I made it!")
>
>
> and a `manifest.scm' with:
>
> (use-modules (gnu) (guix packages)
>            (gnu packages python)
>            (gnu packages python-xyz))
>
> (packages->manifest (list python python-pip))
>
>
> I can get the expected output by running:
> `guix environment --pure --ad-hoc python python-pip -- python3 hi.py' =>
>> halfwaypoint
>> I made it!

It seems that two pip versions don't cohabit very well.  The same
happens if you install pip via 'pip install --user pip' (e.g., to
~/.local/bin) and try to use it.

You could try using the pip version that comes bundled with Python
itself (e.g, not installing python-pip in the same profile); if it's the
only one, it should work.

HTH,

Maxim