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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_nvram(self, nvram):
 """ Sets amount of NVRAM allocated to this router :param nvram: amount of NVRAM in Kbytes (integer) """


        if self._nvram == nvram:
            return

        yield from self._hypervisor.send('vm set_nvram "{name}" {nvram}'.format(name=self._name, nvram=nvram))
        log.info('Router "{name}" [{id}]: NVRAM updated from {old_nvram}KB to {new_nvram}KB'.format(name=self._name,
                                                                                                    id=self._id,
                                                                                                    old_nvram=self._nvram,
                                                                                                    new_nvram=nvram))
        self._nvram = nvram