django bulk_update_or_create work in progress

gistfile1.txt

    def bulk_update_or_create(self, channels, *key_fields):
        if len(key_fields) == 1:
            key_field = key_fields[0]
            key_to_object_mapping = {channel[key_field]: channel for channel in channels}
            lookup = {'{}__in'.format(key_field): list(key_to_object_mapping)}
            existing = self.filter(**lookup)
            existing_keys = existing.values_list(key_field, flat=True)
            to_create = [self.model(**channel) for channel in channels
                         if channel[key_field] not in existing_keys]
            self.bulk_create(to_create, batch_size=1000)

            for key in existing_keys:
                lookup = {key_field: key}
                self.filter(**lookup).update(**key_to_object_mapping[key])
        else:
            raise NotImplementedError()
        pass