In Python, you can define functions with optional arguments — that is, arguments that you don’t need to state explicitly afterwards — by providing a default value.

If you want to learn Python, a number of free or low-cost resources can help you get started.

This article is adapted from an edition of our Off the Charts newsletter originally published in October 2021. Off the Charts is a weekly, subscriber-only guide to The Economist’ s award-winning ...

In Python, the mere act of making a function call incurs a relatively large amount of overhead. If some function is called repeatedly in a tight loop, even if it isn’t a long-running function ...

Take advantage of caching and the lru_cache decorator to relieve your Python functions from repetitive heavy lifting.