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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 move_to(self, target, position='first-child'):
 """Invalidate cache when moving"""


        # Invalidate both in case position matters,
        # otherwise only target is needed.
        self.invalidate()
        target.invalidate()
        super(Page, self).move_to(target, position=position)