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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 _register_self(self, logfile, key=JobDetails.topkey, status=JobStatus.unknown):
 """Runs this link, captures output to logfile, and records the job in self.jobs"""

        fullkey = JobDetails.make_fullkey(self.full_linkname, key)
        if fullkey in self.jobs:
            job_details = self.jobs[fullkey]
            job_details.status = status
        else:
            job_details = self._register_job(key, self.args, logfile, status)