Update the given model to use the current database. Do it also for all
        of its subclasses if they share the same database. (so it's easy to
        call use_database on an abstract model to use the new database for all
        subclasses)

def _use_for_model(self, model):
        """
        Update the given model to use the current database. Do it also for all
        of its subclasses if they share the same database. (so it's easy to
        call use_database on an abstract model to use the new database for all
        subclasses)
        """
        original_database = getattr(model, 'database', None)

        def get_models(model):
            """
            Return the model and all its submodels that are on the same database
            """
            model_database = getattr(model, 'database', None)
            if model_database == self:
                return []
            models = [model]
            for submodel in model.__subclasses__():
                if getattr(submodel, 'database', None) == model_database:
                    models += get_models(submodel)
            return models

        # put the model and all its matching submodels on the new database
        models = get_models(model)
        for _model in models:
            if not _model.abstract:
                self._add_model(_model)
                del original_database._models[_model._name]
            _model.database = self

        # return updated models
        return models