Meaning of using commas and underscores with Python assignment operator?

Question

Reading through Peter Norvig\'s Solving Every Sudoku Puzzle essay, I\'ve encountered a few Python idioms that I\'ve never seen before.

I\'m aware that a function can

Answer 1

You can use the trailing comma in a tuple like this:

>>> (2,)*2
(2, 2)

>>> (2)*2
4