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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 ancestor(self):
 """This browse node's immediate ancestor in the browse node tree. :return: The ancestor as an :class:`~.AmazonBrowseNode`, or None. """

        ancestors = getattr(self.parsed_response, 'Ancestors', None)
        if hasattr(ancestors, 'BrowseNode'):
            return AmazonBrowseNode(ancestors['BrowseNode'])
        return None