Message 334963 - Python tracker

Also, for completeness (since discussion is getting split), please see my proposal to move SharedMemoryManager and SharedMemoryServer into multiprocessing.managers namespace and rename shared_memory.py to _shared_memory.py:
https://mail.python.org/pipermail/python-dev/2019-February/156235.html
Also, it appears ShareableList should be register()ed against SharedMemoryManager.