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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 get_job_by_id(job_id, conn=None):
 """returns the job with the given id :param job_id: <str> id of the job :param conn: <rethinkdb.DefaultConnection> :return: <dict> job with the given id """

    job = RBJ.get(job_id).run(conn)
    return job