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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def delete(self):
 r"""Delete this node from the parse tree. Where applicable, this will remove all descendants of this node from the parse tree. \textit{}\textit{keep me!} \textit{keep me!} """


        # TODO: needs better abstraction for supports contents
        parent = self.parent
        if parent.expr._supports_contents():
            parent.remove(self)
            return

        # TODO: needs abstraction for removing from arg
        for arg in parent.args:
            if self.expr in arg.contents:
                arg.contents.remove(self.expr)