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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_chassis(self, chassis):
 """ Sets the chassis. :param: chassis string: 1720, 1721, 1750, 1751 or 1760 """


        yield from self._hypervisor.send('c1700 set_chassis "{name}" {chassis}'.format(name=self._name, chassis=chassis))

        log.info('Router "{name}" [{id}]: chassis set to {chassis}'.format(name=self._name,
                                                                           id=self._id,
                                                                           chassis=chassis))

        self._chassis = chassis
        self._setup_chassis()