Results 2 issues of Raven

On systems with Python version 3.11 or later, WAF builds fail with the error `ValueError: invalid mode: 'rUb'`. This is because the `'U'` file mode has been [removed in Python...

Ratatouille cannot be installed on systems with Python 3.11 or later, due to termbox using an outdated version of waf. See https://github.com/nsf/termbox/issues/136 and https://github.com/ndreynolds/ex_termbox/issues/14