What does this Python snippet output?

Console output

Why

The literal `"a\tb"` holds a real tab character, but `!r` formats the value with repr(), which renders non-printing characters as their escape sequences. So instead of an actual tab you see the literal backslash-t, and the whole thing is wrapped in quotes: `'a\tb'`. repr() is designed to produce an unambiguous, round-trippable representation, which is why it un-renders the tab.