Exception in thread Thread-1:
Traceback (most recent call last):
  File "/usr/lib/python3.8/threading.py", line 932, in _bootstrap_inner
    self.run()
  File "/usr/lib/python3.8/threading.py", line 870, in run
    self._target(*self._args, **self._kwargs)
  File "/home/haok2/yiwa/venv/lib/python3.8/site-packages/werkzeug/serving.py", line 996, in inner
    srv = make_server(
  File "/home/haok2/yiwa/venv/lib/python3.8/site-packages/werkzeug/serving.py", line 847, in make_server
    return ThreadedWSGIServer(
  File "/home/haok2/yiwa/venv/lib/python3.8/site-packages/werkzeug/serving.py", line 732, in __init__
    real_sock = socket.fromfd(fd, self.address_family, socket.SOCK_STREAM)
  File "/usr/lib/python3.8/socket.py", line 543, in fromfd
    nfd = dup(fd)
OSError: [Errno 9] Bad file descriptor