AttributeError: module 'aiosip' has no attribute 'WS'

[divinj]

I installed aiosip using pip3. I am trying to run https://github.com/Eyepea/aiosip/blob/master/examples/call/client.py

Running into: DEBUG:asyncio:Using selector: KqueueSelector Traceback (most recent call last): File "aiosip-test.py", line 83, in main() File "aiosip-test.py", line 70, in main loop.run_until_complete(start(app, aiosip.UDP, args.duration)) File "/usr/local/Cellar/python/3.7.6_1/Frameworks/Python.framework/Versions/3.7/lib/python3.7/asyncio/base_events.py", line 583, in run_until_complete return future.result() File "aiosip-test.py", line 45, in start if protocol is aiosip.WS: AttributeError: module 'aiosip' has no attribute 'WS'

Any idea what is causing this?