How to use this function (HintPoint_Add), including the optional argument dataTemplate

Age of Empires IV IV - Modding
1

function HintPoint_Add( StackVar where, Boolean bVisible, String hintText, number OPT_height, Integer OPT_actionType, String OPT_iconName, number OPT_priority, Boolean OPT_visibleInFOW, String OPT_dataTemplate )

I want to use a customized dataTemplate, how do I create a new dataTemplate?