类型错误：__call__()缺少1个必需的位置参数：“发送”Django

当我通过 gunicorn（命令：gunicorn --bind :8000 myproject.asgi:application）运行项目时，出现此错误。

错误

Traceback (most recent call last):
  File "/venv/lib/python3.8/site-packages/gunicorn/workers/sync.py", line 136, in handle
    self.handle_request(listener, req, client, addr)
  File "/venv/lib/python3.8/site-packages/gunicorn/workers/sync.py", line 179, in handle_request
    respiter = self.wsgi(environ, resp.start_response)
TypeError: __call__() missing 1 required positional argument: 'send'

asgi.py

import os
from django.core.asgi import get_asgi_application

os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'myproject.settings.base')
django_asgi_app = get_asgi_application()

from channels.auth import AuthMiddlewareStack
from channels.routing import ProtocolTypeRouter, URLRouter

from channels.security.websocket import AllowedHostsOriginValidator
from chats import routing

application = ProtocolTypeRouter({
    "http": django_asgi_app,
    "websocket": AllowedHostsOriginValidator(
        AuthMiddlewareStack(
            URLRouter(
                routing.websocket_urlpatterns
            )
        )
    ),
})

chats.routing.py

from django.urls import re_path

from . import consumers

websocket_urlpatterns = [
    re_path(r'ws/messages/(?P<username>[-:w]+)/$', consumers.ChatConsumer.as_asgi()),
]