Crash because asgiref 3.3.2 makes sure async_to_sync and sync_to_async get passed an awaitable

This is how I think the error happens:

1. create_application in server.py is called.
2. This lambda is created send=lambda message: self.handle_reply(protocol, message)
3. At some point, this lambda is passed into async_to_sync
4. You get an error.

The exact error is:

Traceback (most recent call last):
  File "/home/XYZ/venv/lib/python3.6/site-packages/channels/http.py", line 184, in __call__
    self.send = async_to_sync(send)
  File "/home/XYZ/venv/lib/python3.6/site-packages/asgiref/sync.py", line 105, in __init__
    raise TypeError("async_to_sync can only be applied to async functions.")
TypeError: async_to_sync can only be applied to async functions.

I have tried this with channels==3.0.0. I am on Python 3.6.8.

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[adamchainz]

See #364 for fix.

[adamchainz]

You’ll need asgiref 3.3.3 which added the partial support: https://github.com/django/asgiref/blob/main/CHANGELOG.txt