Twisted - 正确关闭websocket，释放特定端口

Question

目前我正在使用python中的twisted。如何在程序退出时正确关闭websocket实例。只是“reactor.stop”不会做这个工作。 这是代码：

class MyWebSocketProtocol(WebSocketServerProtocol):
def onConnect(self, request):
    self.log("Client connecting: {0}".format(request.peer))

def onOpen(self):
    self.log("WebSocket connection open.")

def onMessage(self, payload, isBinary):
    if payload == "bandwidth":
        content = json.dumps(NetworkMessages.data, ensure_ascii=False).encode('utf8')
        self.sendMessage(content)
        self.log("Sent: {}".format(content))
    else:
        self.log("Unknown request!")

def onClose(self, wasClean, code, reason):
    self.log("WebSocket connection closed: {0}".format(reason))

def log(self, message):
    DataLogger.writeActualData(WebSocketServer.NAME, [message])


class WebSocketServer(object):
def __init__(self,reactor,address,port,dt,wifi):
    factory = WebSocketServerFactory(address)
    factory.protocol = MyWebSocketProtocol
    reactor.listenTCP(port, factory)