python websocket  server在收到接受消息处理完后会默认关闭连接。需要在msg_handler里面加个while true就能一直保持连接了。

   start_server = websockets.serve(msg_handler, "0.0.0.0", 29967)

    asyncio.get_event_loop().run_until_complete(start_server)

    asyncio.get_event_loop().run_forever()

async def msg_handler(websocket, path):

    while True:

        data = await websocket.recv()

        //do someting

        await websocket.send('hey')