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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 parseRangeString(s, convertToZeroBased=False):
 """ Parse a range string of the form 1-5,12,100-200. @param s: A C{str} specifiying a set of numbers, given in the form of comma separated numeric ranges or individual indices. @param convertToZeroBased: If C{True} all indices will have one subtracted from them. @return: A C{set} of all C{int}s in the specified set. """


    result = set()
    for _range in s.split(','):
        match = _rangeRegex.match(_range)
        if match:
            start, end = match.groups()
            start = int(start)
            if end is None:
                end = start
            else:
                end = int(end)
            if start > end:
                start, end = end, start
            if convertToZeroBased:
                result.update(range(start - 1, end))
            else:
                result.update(range(start, end + 1))
        else:
            raise ValueError(
                'Illegal range %r. Ranges must single numbers or '
                'number-number.' % _range)

    return result