python - Django数据库: how to filter objects based on other object's field?

Question

在下面的代码中，如何过滤 capital_listings 以便仅返回首府城市的列表？另外，是否可以去掉中间的capitals_names列表？

capitals = City.objects.filter(status='capital')
capitals_names = [capital.name for capital in capitals]
capital_listings = Listing.objects.filter #???

型号:

class Listing(models.Model):
    city = models.CharField(max_length = 30, default = 'placeholder')
    date_added = models.DateTimeField()

    def __str__(self):
        return self.name

class City(models.Model):
    name = models.CharField(max_length = 30, default = 'placeholder')
    status = models.CharField(max_length = 30, default = 'placeholder')

    def __str__(self):
        return self.name

Answer 1

capital_listings = Listing.objects.filter(city__in=capital_names)