Discount constructor
      const
      Discount({ 
    
- String? checkoutSession,
 - required Coupon coupon,
 - BankAccountCustomerOrId? customer,
 - DateTime? end,
 - required String id,
 - String? invoice,
 - String? invoiceItem,
 - PromotionCodeOrId? promotionCode,
 - required DateTime start,
 - String? subscription,
 
Discount
A discount represents the actual application of a [coupon](https://stripe.com/docs/api#coupons) or [promotion code](https://stripe.com/docs/api#promotion_codes). It contains information about when the discount began, when it will end, and what it is applied to. Related guide: [Applying discounts to subscriptions](https://stripe.com/docs/billing/subscriptions/discounts)
Implementation
const Discount({
  this.checkoutSession,
  required this.coupon,
  this.customer,
  this.end,
  required this.id,
  this.invoice,
  this.invoiceItem,
  this.promotionCode,
  required this.start,
  this.subscription,
});