从threadingtcpserver正常关闭

我创建了一个简单的测试应用程序(python 2.6.1),它运行一个线程化的cpserver,基于这个示例 here . If the client sends a command "bye" I want to shut down the server and exit cleanly from the application. The exit part works OK, but when I try to re-run the app, I get:

socket.error: [Errno 48] Address already in use

我尝试了给出的解决方案 here 用于设置套接字选项,但似乎没有帮助。我尝试了各种方法关闭服务器,但总是得到相同的错误。

知道我做错了什么吗?

import SocketServer
import socket
import sys
import threading
import time

class RequestHandler(SocketServer.BaseRequestHandler):

    def setup(self):
        print("Connection received from %s" % str(self.client_address))
        self.request.send("Welcome!\n")

    def handle(self):
        while 1:
            data = self.request.recv(1024)
            if (data.strip() == 'bye'):
                 print("Leaving server.")
                 self.finish()
                 self.server.shutdown()
                 # None of these things seem to work either
                 #time.sleep(2)
                 #del self.server.socket
                 #self.server.socket.shutdown(socket.SHUT_WR)
                 #self.server.socket.close()
                 #self.server.server_close()
                 break


    def finish(self):
        self.request.send("Goodbye!  Please come back soon.")

if __name__ == "__main__":
       server = SocketServer.ThreadingTCPServer(("localhost", 9999), RequestHandler)
       # This doesn't seem to help.
       #server.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEPORT, 1)
       #server.socket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
       server.serve_forever()
       print("Exiting program.")