How to add corner components on GSHandle by script?

Scripting
1

How to add corner components on GSHandle? The following script shows that the added corner component is not in this GSHandle, it at the origin.

tool = Font.parent.windowController().toolEventDelegate()
for handle in tool.currentTool().extraHandles():
    corner = GSHint()
    corner.name='_corner.abc'
    corner.type = CORNER
    corner.originNode = handle
    Layer.hints.append(corner)

Even if executed
Layer.setExtraHandles_(tool.currentTool().extraHandles())
it not successful either.