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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 _status_change(id, new_status):
 """Update the status of a job The status associated with the id is updated, an update command is issued to the job's pubsub, and and the old status is returned. Parameters id : str The job ID new_status : str The status change Returns ------- str The old status """

    job_info = json.loads(r_client.get(id))
    old_status = job_info['status']
    job_info['status'] = new_status
    _deposit_payload(job_info)

    return old_status