def root(obj, value=None, *args, **named):
    """Get/set root-node reference for nodes/protos"""
    from vrml import node
    if value is not None:
        return node.Node.rootSceneGraph.fset(obj, value, *args, **named)
    else:
        return node.Node.rootSceneGraph.fget(obj, *args, **named)
