def METHOD_NAME(self):
    request = self.request_factory.patch('/api/cars', data={})
    request.user = self.user1
    car_serializer = CarSerializer2(
        instance=self.car, context={'request': request}
    )
    fields = car_serializer.get_fields()
    self.assertIs(fields['year'].context['request'], request)
    self.assertIs(fields['manufacturer'].context['request'], request)