@type t() :: %Paypal.Order.PurchaseUnit.Item{
  category: any() | nil,
  description: String.t() | nil,
  image_url: String.t() | nil,
  name: String.t() | nil,
  quantity: integer() | nil,
  sku: String.t() | nil,
  tax: Paypal.Common.CurrencyValue.t() | nil,
  unit_amount: Paypal.Common.CurrencyValue.t() | nil,
  upc: Paypal.Order.UpcCode.t() | nil,
  url: String.t() | nil
}

The purchase unit has different items and each item has the following information:

• name of the item.
• quantity of the item included in the order.
• description of the item.
• sku is the ID for the item.
• url is the URL for the item.
• category is the category where the item is included.
• image_url is the URL for the image.
• unit_amount is the price for each unit.
• tax is the price for the taxes.
• upc is the UPC EAN code.