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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 print_update(self, stream=sys.stdout, job_stats=None):
 """Print an update about the current number of jobs running """

        if job_stats is None:
            job_stats = JobStatusVector()
            job_det_list = []
            job_det_list += self._scatter_link.jobs.values()

            for job_dets in job_det_list:
                if job_dets.status == JobStatus.no_job:
                    continue
                job_stats[job_dets.status] += 1

        stream.write("Status :\n  Total  : %i\n  Unknown: %i\n" %
                     (job_stats.n_total, job_stats[JobStatus.unknown]))
        stream.write("  Not Ready: %i\n  Ready: %i\n" %
                     (job_stats[JobStatus.not_ready], job_stats[JobStatus.ready]))
        stream.write("  Pending: %i\n  Running: %i\n" %
                     (job_stats[JobStatus.pending], job_stats[JobStatus.running]))
        stream.write("  Done: %i\n  Failed: %i\n" %
                     (job_stats[JobStatus.done], job_stats[JobStatus.failed]))