Support Django 3.0

[snake-soft]

In Django 3 they dropped support for Python2 compatibility APIs:
https://docs.djangoproject.com/en/3.0/releases/3.0/#removed-private-python-2-compatibility-apis

Because of that django-oscar-paypal threw an error when using it with Django3:
ImportError: cannot import name 'python_2_unicode_compatible' from 'django.utils.encoding' (/home/me/.virtualenvs/oscar/lib/python3.7/site-packages/django/utils/encoding.py)

I found the solution for that problem here:
https://forum.djangoproject.com/t/python-2-unicode-compatible/715

In short - The compatibility api is available as standalone package:
https://pypi.org/project/six/

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Are there any other issues known that could avoid the django 3 compatibility?

[Dihfahsih1]

To install oscar with django 3.x, do the following:

pip3 install django-tables2
pip3 install django-oscar==3.0a0
pip3 install Django==3.1.3

[fluxtom]

The latest version of django-oscar-paypal seems to fix the issue, but it is not in pypi yet.

pip3 install git+https://github.com/django-oscar/django-oscar-paypal.git fixed the issue for me.

[laf0rge]

given that it's close to one year since @fluxtom has repored the git master works but is not in pip: Can the pip metadata please be updated?