Someone else mentioned the fact that

    default_result if condition else alternate_result

is pythons form of ternary expression and semantically equivalent other then pythons truthiness boolean testing of objects(empty collections, 0, empty strings, False, None, 0 timedelta evaluate to False, also objects where obj.__nonzero__() returns False (in python3 __nonzero__ is renamed to __bool__)).

I'd like to bring up that while it's a matter of opinion the older ugly ?: syntax is much less readable even when you memorize it. I never use ?: syntax ternary expressions in languages that have them because I always have to look it up. That's why a number of languages prefer python-like versions or forms which emphasize to an even larger degree the fact that its just an if-else as an expression to an even larger degree(so I'd question that it's standard, I'm not 100% it's older either as I think the LISP version is closer to the python version).

CoffeeScript

    s = if condition then "yup" else "nope"

Smalltalk

    abs := x > 0 ifTrue: [ x ] ifFalse: [ x negated ]

Ruby has both versions

Scala a = if (n == 12) "twelve" else "not twelve"

Rust

    let y = if x == 5 { 10 } else { 15 }; // y: i32

Haskell

    fac x = if x==0 then
           1
           else x * fac (x - 1)

(some examples taken from http://rosettacode.org)