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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 pick_free_port(hostname=REDIRECT_HOST, port=0):
 """ Try to bind a port. Default=0 selects a free port. """

    import socket
    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    try:
        s.bind((hostname, port))  # port=0 finds an open port
    except OSError as e:
        log.warning("Could not bind to %s:%s %s", hostname, port, e)
        if port == 0:
            print('Unable to find an open port for authentication.')
            raise AuthenticationException(e)
        else:
            return pick_free_port(hostname, 0)
    addr, port = s.getsockname()
    s.close()
    return port