python的三元运算符

Yes, it was added in
version 2.5. It's frowned upon by some pythonistas, so keep that in mind.

The syntax is:

a if test else b

First

test

is
evaluated, then either

a

or

b

is
returned based on the Boolean value
of

test

;

if

test

evaluates
to True

a

is
returned, else

b

is
returned.

For example:

>>> 'true' if True else 'false'
'true'
>>> 'true' if False else 'false'
'false'

Official documentation:

Conditional
expressions

Is
there an equivalent of C’s ”?:” ternary operator?