Hence the advice to stick to the standard library - because then it doesn't matter all that much. I'm not sure what the full set of environments I've tested my

Hence the advice to stick to the standard library - because then it doesn't matter all that much. I'm not sure what the full set of environments I've tested my Python 3 scripts actually is, but they've run OK on all the various cloud CI systems I've tried, plus my laptops, VMs, and work PCs.