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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 set_system_id(self, system_id):
 """ Sets the system ID. :param system_id: a system ID (also called board processor ID) """


        yield from self._hypervisor.send('{platform} set_system_id "{name}" {system_id}'.format(platform=self._platform,
                                                                                                name=self._name,
                                                                                                system_id=system_id))

        log.info('Router "{name}" [{id}]: system ID updated from {old_id} to {new_id}'.format(name=self._name,
                                                                                              id=self._id,
                                                                                              old_id=self._system_id,
                                                                                              new_id=system_id))
        self._system_id = system_id