Question

What is the explanation for this behavior in Python?

a = 10
b = 20
a and b # 20
b and a # 10

a and b evaluates to 20, while b and a evaluates to 10. Are positive ints equivalent to True? Why does it evaluate to the second value? Because it is second?

Answer 1

The documentation explains this quite well:

The expression x and y first evaluates x; if x is false, its value is returned; otherwise, y is evaluated and the resulting value is returned.

And similarly for or which will probably be the next question on your lips.

The expression x or y first evaluates x; if x is true, its value is returned; otherwise, y is evaluated and the resulting value is returned.