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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_ghost_file(self, ghost_file):
 """ Sets ghost RAM file :ghost_file: path to ghost file """


        yield from self._hypervisor.send('vm set_ghost_file "{name}" {ghost_file}'.format(name=self._name,
                                                                                          ghost_file=shlex.quote(ghost_file)))

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

        self._ghost_file = ghost_file