Python Django ORM用客户分数标注产品

考虑以下Django模型

Customer(models.Model)
    name = models.CharField()

Product(models.Model)
    name = models.CharField()

Score(models.Model)
    points = models.IntegerField()
    customer = models.ForeignKey(Customer)
    product = models.ForeignKey(Product)

我想得到一份所有产品的清单，上面注明：

• 所有客户的总分
• 仅来自当前客户的分数

我能让它在总分中工作，如下所示：

products = Product.objects.annotate(total_points = Sum('score__points')).all()

cus = Cusomter.objects.get(pk=123)
products = Product.objects.annotate(total_points = Sum('score__points'),\
                                    current_customer_points= (Score.points where customer=cus and product = this).all()

但是我不知道如何添加一个只包含当前客户分数的注释（如果客户已经查看了产品，则没有其他注释）。我想要这样的东西：

products = Product.objects.annotate(total_points = Sum('score__points')).all()

cus = Cusomter.objects.get(pk=123)
products = Product.objects.annotate(total_points = Sum('score__points'),\
                                    current_customer_points= (Score.points where customer=cus and product = this).all()