Language design questions are also about how to not make languages complex and add too many features to them. I'd argue that creating or modifying a language s

Language design questions are also about how to not make languages complex and add too many features to them. I'd argue that creating or modifying a language should be a last resort. After all, there's nothing to stop you from implementing this in Python right now with thread-local storage, and I'm sure you could achieve the same effect with other languages if you don't like the idea of the GIL or slow interpreted languages.