Syntax error

I want to make a date field (Actual Close Date) auto populate as today's date if the sales status on the drop down has a selected status of closed lost or closed won but I'm receiving an error - here is what I have so far but I'm receiving an error  Syntax Error, no close parentheses found and I'm not sure what I'm missing?  ifElse(isInList($sales_stage,createList("Close Won","Closed Lost"),today()," ")