Get 'Roto' item type

I’m trying to return every ‘item’ type within a ‘roto context’.
Since there’s no such function like ‘isBezierCurve’, 'isLayer() or 'isStroke(), i tried to use the ‘type()’ to get item’s class.
But they’re all of ‘ItemBase’.
How do i get to know if they are of ‘BezierCurve’ or ‘Layer’ subclass ?

Ok, found it.
We write the way to do it later.