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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 _get_cached_response(self):
 """Returns a file object of the cached response."""


        if not self._is_cached():
            response = self._download_response()
            self.cache.set_xml(self._get_cache_key(), response)

        return self.cache.get_xml(self._get_cache_key())