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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 iter_last_tour(tourfile, clm):
 """ Extract last tour from tourfile. The clm instance is also passed in to see if any contig is covered in the clm. """

    row = open(tourfile).readlines()[-1]
    _tour, _tour_o = separate_tour_and_o(row)
    tour = []
    tour_o = []
    for tc, to in zip(_tour, _tour_o):
        if tc not in clm.contigs:
            logging.debug("Contig `{}` in file `{}` not found in `{}`"
                          .format(tc, tourfile, clm.idsfile))
            continue
        tour.append(tc)
        tour_o.append(to)
    return tour, tour_o