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Python

Posted by Kevin Li
Kevin Li
2,634 Points

"Return" in Python

Hi, I don't really get how return works in Python, and how to use it. For example, I was stuck on a challenge (the last one I think in Python Basics): They included for me "return not num % 2" when num % 2 was 1. How can you use these return blocks in an "if" block? Do you know what lesson explains the return method?

1 Answer

Steven Parker
Steven Parker
243,318 Points
Steven Parker
Steven Parker
243,318 Points

The return statement in Python is very similar to other languages. It is only used inside a function, and it causes the function execution to end. Any parameter it is given is evaluated and passed back to the caller of the function as the function's value.

So a function that contains "return not num % 2" will give the caller the result of evaluating "not num % 2", which means the function's value will be true when num is even, and false when num is odd.

Does that help?

Kevin Li
Kevin Li
2,634 Points

Ok, so does this work?

import random

start = 5

def even_odd(num):

# If % 2 is 0, the number is even.

# Since 0 is falsey, we have to invert it with not.

if num % 2 == 1:

    return not num % 2

elif num % 2 == 0:

    return num % 2

while start:

num = random.randint(1, 99)

if not num % 2:

    print("{} is even".format(num))

elif num % 2:

    print("{} is odd".format(num))
Kevin Li
Kevin Li
2,634 Points

Thanks. It turned out to be a simple mistake I overlooked.