Channels ERROR: Task was destroyed but it is pending!

[Anh Tran]

I'm using Channels 2.1.3 with ASGI server is `uvicorn`.

ERROR: Task was destroyed but it is pending!
task: <Task pending coro=<Queue.get() done, defined at /opt/python-3.6.6/lib/python3.6/asyncio/queues.py:155> wait_for=<Future cancelled>>
ERROR: Exception in ASGI application
Traceback (most recent call last):
  File "/home/admin/webapps/yy/venv3/lib/python3.6/site-packages/uvicorn/protocols/websockets/websockets_impl.py", line 140, in run_asgi
    result = await asgi(self.asgi_receive, self.asgi_send)
  File "/home/admin/webapps/yy/venv3/lib/python3.6/site-packages/channels/sessions.py", line 175, in __call__
    return await self.inner(receive, self.send)
  File "/home/admin/webapps/yy/venv3/lib/python3.6/site-packages/channels/middleware.py", line 41, in coroutine_call
    await inner_instance(receive, send)
  File "/home/admin/webapps/yy/venv3/lib/python3.6/site-packages/channels/consumer.py", line 54, in __call__
    await await_many_dispatch([receive, self.channel_receive], self.dispatch)
  File "/home/admin/webapps/yy/venv3/lib/python3.6/site-packages/channels/utils.py", line 57, in await_many_dispatch
    await task
  File "/home/admin/webapps/yy/venv3/lib/python3.6/site-packages/channels/utils.py", line 49, in await_many_dispatch
    result = task.result()
  File "/home/admin/webapps/yy/venv3/lib/python3.6/site-packages/uvicorn/protocols/websockets/websockets_impl.py", line 223, in asgi_receive
    data = await self.recv()
  File "/home/admin/webapps/yy/venv3/lib/python3.6/site-packages/websockets/protocol.py", line 336, in recv
    loop=self.loop, return_when=asyncio.FIRST_COMPLETED)
  File "/opt/python-3.6.6/lib/python3.6/asyncio/tasks.py", line 311, in wait
    fs = {ensure_future(f, loop=loop) for f in set(fs)}
  File "/opt/python-3.6.6/lib/python3.6/asyncio/tasks.py", line 311, in <setcomp>
    fs = {ensure_future(f, loop=loop) for f in set(fs)}
  File "/opt/python-3.6.6/lib/python3.6/asyncio/tasks.py", line 526, in ensure_future
    raise TypeError('An asyncio.Future, a coroutine or an awaitable is '
TypeError: An asyncio.Future, a coroutine or an awaitable is required