def _read_composites(self, compositor_nodes):
        """Read (generate) composites."""
        keepables = set()
        for item in compositor_nodes:
            self._generate_composite(item, keepables)
        return keepables
def _read_composites ( self , compositor_nodes ) : keepables = set ( ) for item in compositor_nodes : self . _generate_composite ( item , keepables ) return keepables
Read (generate) composites.