我有一个Django项目来实现折扣码。模型如下：

class CouponCode(models.Model):
    max_usage = models.PositiveSmallIntegerField()
    max_usage_per_user = models.PositiveSmallIntegerField(default=1)
    code = CharField(max_length=10, unique=True)
    discount_percent = models.PositiveSmallIntegerField(default=0, validators=MaxValueValidator(100)])
    max_discount_amount = models.PositiveIntegerField(default=0)
    is_active = models.BooleanField(default=True)
    start_date = models.DateTimeField(null=True, blank=True)
    end_date = models.DateTimeField(null=True, blank=True)
    minimum_price = models.PositiveBigIntegerField(default=0)

class UsedCode(models.Model):
    customer = models.PositiveBigIntegerField(verbose_name='customer id')
    coupon = models.ForeignKey(CouponCode, on_delete=models.PROTECT)
    order_id = models.PositiveIntegerField()

    @classmethod
    def has_reached_max_usage_for_user(cls, coupon, user):
        usages = cls.objects.filter(coupon=coupon, customer=user).count()
        if usages < coupon.max_usage_per_user:
            return False
        return True

    @classmethod
    def has_reached_max_usage(cls, coupon):
        usages = cls.objects.filter(coupon=coupon).count()
        if usages < coupon.max_usage:
            return False
        return True

字符串
每次使用优惠券代码创建订单时，都会创建UsedCode对象。我想实现一个功能，如果订单被取消，优惠券代码可以重复使用。我宁愿不删除对象，这样我就可以跟踪数据。