Could tkinter be added?

Context

QElectroTech is working on flatpaking their app. They use the KDE runtime, as the app is built with C++/Qt.

However, it has an optional external plugin they'd like to add, which is written in Python and uses tkinter.

Description

Tkinter is not part of the Sdk, and it's not even trivial to add it for apps because it is not distributed as a Python module: it is part of Python itself.

If we decided to provide it in the runtime we'd probably have to add its dependencies as well, mostly Tk.

Would we add it to the runtime itself? In an extension?

Acceptance Criteria

If we decide to add it, then the following should work:

$ flatpak run org.freedesktop.Platform
$ [📦 org.freedesktop.Platform ~]$ python3
>>> import tkinter