Handle NoneType exit event

[jkroll-deepgram]

Proposed changes

Fix a bug where is_set() is being called on self._exit_event when it has a value of None, causing an AttributeError that bubbles up as an error in application code. To fix, require that self._exit_event is not None before calling self._exit_event.is_set().

I do also see in other spots that events are being initialized as asyncio.Event(). Should the exit event be instantiated as self._exit_event = asyncio.Event() instead of self._exit_event = None, so self._exit_event is never None in the first place?

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• [x] Bugfix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [ ] Documentation update or tests (if none of the other choices apply)

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Further comments

[dvonthenen]

I do also see in other spots that events are being initialized as asyncio.Event(). Should the exit event be instantiated as self._exit_event = asyncio.Event() instead of self._exit_event = None, so self._exit_event is never None in the first place?

I can take a look at this and double check.

[dvonthenen]

I suspect that the event should have been reset and not deleted is the problem. This might have been a copy and paste gone too far. Confirming this now.