I need to define some permissions and groups that are used in the models and the views. I know how to do it with permissions (define them in the "Meta" of some models), but it is not clear to me how to do it with groups. Maybe the right thing to do is not to use the groups provided in Django's Auth, but to create some new models to handle these "constant" groups.
I also tried to create these groups as "initial data" (https://docs.djangoproject.com/en/1.7/howto/initial-data/), but this solution does not seem very clean to me.