How to use actual_cost_hook for Average Cost

 Hi Experts,

per Oracle Cost Mangement user guide,

"Cost Management calls the transaction cost extensions for most
transactions at the time of processing. The three exceptions are Average
Cost Update transactions, in an average costing organization, a
Common Issue to Project Work in Process transaction, in a project
manufacturing costing organization, and Interorganization Transfer
transactions.
You should ensure that the cost element by level costs is in
MTL_CST_ACTUAL_COST_DETAILS according to your requirements.
Return Values of Function
When this extension is called, the system determines whether it has been
implemented and returns a value accordingly. The return values are as