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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_network(self, machines, local_listen_port=12400, listen_time_out=120, num_machines=1):
 """Set the network configuration. Parameters machines : list, set or string Names of machines. local_listen_port : int, optional (default=12400) TCP listen port for local machines. listen_time_out : int, optional (default=120) Socket time-out in minutes. num_machines : int, optional (default=1) The number of machines for parallel learning application. Returns ------- self : Booster Booster with set network. """

        _safe_call(_LIB.LGBM_NetworkInit(c_str(machines),
                                         ctypes.c_int(local_listen_port),
                                         ctypes.c_int(listen_time_out),
                                         ctypes.c_int(num_machines)))
        self.network = True
        return self