name of skill function get list of master children layout cells used in current design

Does Cadence Virtuoso have a skill function to get list of master children layout cells used in current design?

I've tried to work with

ddGetObjChildren

but this function returns children of datatypes for my top cell: schematic, abstract , etc. I need list of layout children masters used in this top cell.

I got solution from Cadence Support Team!

procedure( TrHierTraversal( cellView cellList )
    foreach( master cellView~>instances~>master 
        let( ( nextCellView )
            nextCellView =  master
            cond(
                ( !nextCellView nil )
                ( member( nextCellView cellList ) nil )
                ( t 
                  cellList = TrHierTraversal( nextCellView cons( nextCellView cellList ) )
                ) ; t
                ) ; cond
           ) ; let
        ) ; foreach 
    cellList ;;; return value - list of all master cells in hierarchy
) ; procedure

expansion = TrHierTraversal( dbOpenCellViewByType( "MAIN_LIB" "mux" "layout" ) nil )

foreach( item expansion printf("%L" item~>cellName))