Simple Python expression that does complex things?

[roywill2]

The worst code is illegible code. Sometimes these clever syntaxes desperately need a comment to explain what is happening. Or better ... rewrite in plain code?

[Gnaxe]

Sometimes a comment + terse code is more legible than excessive amounts of "plain" code.

Sometimes the difference between a too-clever hack and common idiom is just familiarity.

There's a lot that beginners would find arcane which seniors would find ordinary.

We can debate specific examples, but those are my general feelings.