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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 _port_not_in_use():
 """Use the port 0 trick to find a port not in use."""

    s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    port = 0
    s.bind(('', port))
    _, port = s.getsockname()
    return port