When I use a dropdown to pick a part number how do I get the equivalent of this VB code to work in ZOHO???

Private Sub PickPartID_AfterUpdate()
Description = DLookup("[Description]", "TblParts", "[ID] = PickPartID")
Retail = DLookup("[Retail]", "TblParts", "[ID] = PickPartID")
Price = DLookup("[Price]", "TblParts", "[ID] = PickPartID")
Cost = DLookup("[Cost]", "TblParts", "[ID] = PickPartID")