How to use GROUP BY in Django without using values()?

Question

I am trying to GROUP BY with Django ORM:

sub = (
        Participant.objects
        .values('category')
        .annotate(
            average=Avg(F('price')),
        )
    )

It works as expected BUT the queryset does not contains instances of the model anymore. If contains dicts because values() has been called.

How can do a group by query and get a regular queryset (with model instances)?