@type t() :: %Stripe.Discount{
  checkout_session: binary() | nil,
  customer: (binary() | Stripe.Customer.t() | Stripe.DeletedCustomer.t()) | nil,
  end: integer() | nil,
  id: binary(),
  invoice: binary() | nil,
  invoice_item: binary() | nil,
  object: binary(),
  promotion_code: (binary() | Stripe.PromotionCode.t()) | nil,
  source: term(),
  start: integer(),
  subscription: binary() | nil,
  subscription_item: binary() | nil
}

The discount type.

• checkout_session The Checkout session that this coupon is applied to, if it is applied to a particular session in payment mode. Will not be present for subscription mode.
• customer The ID of the customer associated with this discount.
• end If the coupon has a duration of repeating, the date that this discount will end. If the coupon has a duration of once or forever, this attribute will be null.
• id The ID of the discount object. Discounts cannot be fetched by ID. Use expand[]=discounts in API calls to expand discount IDs in an array.
• invoice The invoice that the discount's coupon was applied to, if it was applied directly to a particular invoice.
• invoice_item The invoice item id (or invoice line item id for invoice line items of type='subscription') that the discount's coupon was applied to, if it was applied directly to a particular invoice item or invoice line item.
• object String representing the object's type. Objects of the same type share the same value.
• promotion_code The promotion code applied to create this discount.
• source
• start Date that the coupon was applied.
• subscription The subscription that this coupon is applied to, if it is applied to a particular subscription.
• subscription_item The subscription item that this coupon is applied to, if it is applied to a particular subscription item.