How to clear the script parameters Joint nodeA and nodeB?

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:information_source: Attention Topic was automatically imported from the old Question2Answer platform.
:bust_in_silhouette: Asked By Tort
:warning: Old Version Published before Godot 3 was released.

How to clear the script parameters Joint nodeA and nodeB?
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:bust_in_silhouette: Reply From: ericdl 
var joint = get_node("Joint").set_node_a("")