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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 atlasdb_renew_peer( peer_hostport, now, con=None, path=None ):
 """ Renew a peer's discovery time """

    with AtlasDBOpen(con=con, path=path) as dbcon:
        if now is None:
            now = time.time()

        sql = "UPDATE peers SET discovery_time = ? WHERE peer_hostport = ?;"
        args = (now, peer_hostport)

        cur = dbcon.cursor()
        res = atlasdb_query_execute( cur, sql, args )
        dbcon.commit()

    return True