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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 _parse_port_ranges(pool_str):
 """Given a 'N-P,X-Y' description of port ranges, return a set of ints."""

    ports = set()
    for range_str in pool_str.split(','):
        try:
            a, b = range_str.split('-', 1)
            start, end = int(a), int(b)
        except ValueError:
            log.error('Ignoring unparsable port range %r.', range_str)
            continue
        if start < 1 or end > 65535:
            log.error('Ignoring out of bounds port range %r.', range_str)
            continue
        ports.update(set(range(start, end + 1)))
    return ports