Link a local clone of django into a virtualenv of an empty folder
Start with a local project, django-admin startproject MYPROJECT
Change LANGUAGE_CODE = 'de-de' in settings.py
Edit: <djangoclone>/django/contrib/admin/locale/de/LC_MESSAGES/django.po
In the <djangoclone>/django/contrib folder, run django-admin compilemessages
Restart django webserver.
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django-admin makemessages -l ur_LC doesn't work, generates functions that raise ValueErrors with Plurals
Editing local copies of locale versions known to work is a dirty dirty hack