错误：通常只允许使用每个套接字地址（协议/网络地址/端口）

我试图用Python编写TCP客户端 - 服务器程序 . 一旦 Build 连接，服务器就会回送（所有CAPS）客户端发送到服务器的任何内容 . 服务器应该能够使用线程并行地一次处理多个请求 .

但是，只要我运行server.py文件，我就会收到错误：

通常只允许使用每个套接字地址（协议/网络地址/端口） .

我试过更改端口号，也尝试使用setsockopt（SOL_SOCKET，SO_REUSEADDR，1）

我仍然得到错误 . 请帮忙 . 到目前为止，这是我的代码 .

#!/usr/bin/python

import socket 
import sys 
import threading

class Server: 
    def __init__(self): 
        self.host = ''
        self.port = 12345 
        self.backlog = 5 
        self.size = 1024 
        self.server = None 
        self.threads = []       #initalizes a list of client threads

    def open_socket(self): 
        try: 
            self.server = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
            self.server.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)
            self.server.bind((self.host,self.port)) 
            self.server.listen(5) 
        except socket.error, (value,message): 
            if self.server: 
                self.server.close() 
            print "Could not open socket: " + message 
            sys.exit(1) 

    def run(self): 
        self.open_socket() 
        running = 1 
        while running:
            # handle the server socket 
            c = Client(self.server.accept()) 
            c.start() 
            self.threads.append(c) 

        #close all threads 

        self.server.close() 
        for c in self.threads: 
            c.join()

class Client(threading.Thread): 
    def __init__(self,(client,address)): 
        threading.Thread.__init__(self) 
        self.client = client 
        self.address = address 
        self.size = 1024

    def run(self):
        running = 1
        while running:
            data = client.recv(size)
            if data == 'Quit':
                break
            else:
                print 'Received : ', data
                newdata = data.upper()
                client.send(newdata)
        print '\nConnection Closed'
        client.close()
        running = 0

if __name__ == "__main__": 
    s = Server() 
    s.run()