python - Function that returns a tuple gives TypeError: 'NoneType' object is not iterable -

what error mean? i'm trying make function returns tuple. i'm sure i'm doing wrong. appreciated.

from random import randint = randint(1,3) b = randint(1,3) def make_them_different(a,b):     while == b:         = randint(1,3)         b = randint(1,3)         return (a,b) new_a, new_b = make_them_different(a,b) 

your code returns none if a != b.

since, have return statement inside while loop, if while loop never gets executed, python returns default value of none cannot assigned new_a, new_b.

>>> print make_them_different(2, 3) none  >>> print make_them_different(2, 2) (2, 1) 

you fix returning default values (since different , that's intend do)

def make_them_different(a,b):     while == b:         = randint(1,3)         b = randint(1,3)     return (a,b)  # dedented return line. 

demo -

>>> make_them_different(2, 2) (3, 2) >>> make_them_different(2, 3) (2, 3)