def __nonzero__(self):
        """
            Return True if all the items still exist on the filesystem,
            false otherwise. Also returns false if there are no items
            yet (i.e., it's an empty list).
        """
        if len(self) > 0:
            for name in self:
                if not os.path.exists(name):
                    return False
            return True
        else:
            return False

            Return True if all the items still exist on the filesystem,
            false otherwise. Also returns false if there are no items
            yet (i.e., it's an empty list).
        
recipes/Python/259147_FSList/recipe-259147.py