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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 parse(self, target):
 """ Update root and parent context. """

        super(VarDefinition, self).parse(target)
        if isinstance(self.parent, ParseNode):
            self.parent.ctx.update({self.name: self.expression.value})
        self.root.set_var(self)