Python 3.15 introduces an immutable or ‘frozen’ dictionary that is useful in places ordinary dicts can’t be used.

Python, for all its power and popularity, has long lacked a form of flow control found in other languages—a way to take a value and match it elegantly against one of a number of possible conditions.

Data work in 2026 asks for more than chart building. Professionals are expected to clean data, query databases, explain ...