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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 set_trace(addr=DEFAULT_ADDR, port=DEFAULT_PORT):
 """ Set a trace point using the remote debugger """

    atexit.register(close_port, port)
    try:
        log("Starting a remote python debugger session on %s:%s" % (addr,
                                                                    port))
        open_port(port)
        debugger = Rpdb(addr=addr, port=port)
        debugger.set_trace(sys._getframe().f_back)
    except Exception:
        _error("Cannot start a remote debug session on %s:%s" % (addr,
                                                                 port))