Using PyObjC 4.0.1 on macOs 10.10.3 we're seeing an error below that doesn't occur on macOS 10.12.6:
initWithDelegate_queue_options_(self, queue_ptr, None) ValueError: depythonifying 'pointer', got 'OS_dispatch_queue'
A standalone testcase is here: https://gist.github.com/WayneKeenan/8ce4d841158909ad441dc7312637a064
I would be interested to know if it can be worked around when using PyObjC 4.0.1 on macOS 10.10.x ?
Perhaps the upcoming PyObjC 4.1's added dispatch support means the workaround will go away and I wonder that because the Python/ObjC conversion isn't needed all will be ok on 10.10 as it is on 10.12 (?)