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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_status_self(self, key=JobDetails.topkey, status=JobStatus.unknown):
 """Set the status of this job, both in self.jobs and in the `JobArchive` if it is present. """

        fullkey = JobDetails.make_fullkey(self.full_linkname, key)
        if fullkey in self.jobs:
            self.jobs[fullkey].status = status
            if self._job_archive:
                self._job_archive.register_job(self.jobs[fullkey])
        else:
            self._register_self('dummy.log', key, status)