I haven't used Coconut beyond some dabbling last time it made HN's frontpage, so someone with more experience may be able to provide a better answer. However, the syntax is based on Python 3, and they use their own builtins for both Python 2 and 3 to maintain compatibility. Some functionality can't be back-ported to Python 2 (tuple unpacking with *, f strings, etc.), and there is more info about that at the link below.

https://coconut.readthedocs.io/en/master/DOCS.html#compatibl...