code: function Payment() {
      /**
       * The total value
       * @member
       */
      this.total = null;
      /**
       * The subtotal value
       * @member
       */
      this.subtotal = null;
      /**
       * The formattedTotal value
       * @member
       */
      this.formattedTotal = null;
      /**
       * The formattedSubtotal value
       * @member
       */
      this.formattedSubtotal = null;
      /**
       * The currency value
       * @member
       */
      this.currency = null;
      /**
       * The coupon of value
       * @member
       * @type { Coupon }
       */
      this.coupon = Object.create(Coupon.prototype);
      /**
       * The tax of value
       * @member
       * @type { Tax }
       */
      this.tax = Object.create(Tax.prototype);
      /**
       * The shipping of value
       * @member
       * @type { Shipping }
       */
      this.shipping = Object.create(Shipping.prototype);
  
  }
docs: The Payment class
  @constructor
  @alias Payment