code: func (r Billing_Order_Cart) DeleteCart() (resp bool, err error) {
  	err = r.Session.DoRequest("SoftLayer_Billing_Order_Cart", "deleteCart", nil, &r.Options, &resp)
  	return
  }
docs: // If a cart is no longer needed, it can be deleted using this service. Once a cart has been deleted, it cannot be retrieved again.