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Python Python Basics (2015) Letter Game App Even or Odd Loop

Why do we invert with not because 0 is falsey

I don't understand why they do this? How does it help? Why does it matter?

# Since 0 is falsey, we have to invert it with not.
    return not num % 2
even.py
import random
def even_odd(num):
    # If % 2 is 0, the number is even.
    # Since 0 is falsey, we have to invert it with not.
    return not num % 2

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,426 Points

It depends solely on the desired result from the even_odd function. The comments imply the return value should be True if the num is even. Using the modulo 2 math, an even number results in a 0 (logically False) and an odd number results in a 1 (logically True). The not is used to reverse the logical Boolean value to match the desired result: evens become True and odds become False.

Post back if you have more questions!!