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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 finish(db, job_id, status):
 """ Set the job columns `is_running`, `status`, and `stop_time`. :param db: a :class:`openquake.server.dbapi.Db` instance :param job_id: ID of the current job :param status: a string such as 'successful' or 'failed' """

    db('UPDATE job SET ?D WHERE id=?x',
       dict(is_running=False, status=status, stop_time=datetime.utcnow()),
       job_id)