Matthew, this tracker issue has been closed for over 10 years; posting new questions or comments to such is unlikely to get a response (I just happened to see your comment in passing). If you believe you have identified a new issue with current versions of Python, you should search for newer issues and, if appropriate, open a new one with a reference to this one. However, before doing that, I would do a web search on "cannot import name 'SemLock'"; you should find a number of references to situations that seem similar to yours with the cause being the lack of a working sem_open implementation as noted in the ImportError message, a condition that might just be a system configuration issue on the build system. Good luck!