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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 main(argv):
 """If passed an arg, treat it as a PID, otherwise portpicker uses getpid."""

    port = pick_unused_port(pid=int(argv[1]) if len(argv) > 1 else None)
    if not port:
        sys.exit(1)
    print(port)