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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 _range2cols(areas):
 """ Convert comma separated list of column names and ranges to indices. Parameters areas : str A string containing a sequence of column ranges (or areas). Returns ------- cols : list A list of 0-based column indices. Examples -------- [0, 1, 2, 3, 4] [0, 2, 25, 26, 27] """

    cols = []

    for rng in areas.split(","):
        if ":" in rng:
            rng = rng.split(":")
            cols.extend(lrange(_excel2num(rng[0]), _excel2num(rng[1]) + 1))
        else:
            cols.append(_excel2num(rng))

    return cols