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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 hard_reboot_instance(self):
 """Stop then start the instance."""

        self._stop_instance()
        self._start_instance()
        self._set_instance_ip()
        self.logger.debug('IP of instance: %s' % self.instance_ip)
        ipa_utils.clear_cache()