UpdateView that handles "create" as well

gistfile1.py

from myapp.models import MyModel, RelatedModel
from django.views.generic import UpdateView


class ModelCreateUpdateView(UpdateView):
    model = MyModel

    def get_object(self, *args, **kwargs):
        related_id = self.kwargs.get('related_id')
        related_model = RelatedModel.objects.get(pk=related_id)
        my_object, _ = MyModel.objects.get_or_create(user=self.request.user,
                                              related_model=related_model)
        return my_object