code: func (r Billing_Order_Item) GetPreset() (resp datatypes.Product_Package_Preset, err error) {
  	err = r.Session.DoRequest("SoftLayer_Billing_Order_Item", "getPreset", nil, &r.Options, &resp)
  	return
  }
docs: // Retrieve The SoftLayer_Product_Package_Preset related to this order item.