AS3 :: Flash - Removing The Event Listeners?

I have a basic question about manually removing event listeners in actionscript 3.If I have a function like:

private function doStuff(event : Event):void
{
//let them save
var f:FileReference = new FileReference();

[code]...

How do I remove the event listeners when the saveDone function is called? Normally I just change the "add" to "remove" like:

f.removeEventListener(Event.COMPLETE,saveDone);

However, f is a local variable, and I can't get to it after the doStuff function ends.

private function saveDone(ev:Event){
f.removeEventListener(Event.COMPLETE,saveDone);
}