I would like to shuffle the order of the elements in a list.
from random import shuffle
words = ['red', 'adventure', 'cat', 'cat']
shuffled = shuffle(words)
print(shuffled) # expect new order for, example ['cat', 'red', 'adventure', 'cat']
As response I get None, why?
It's because random.shuffle shuffles in place and doesn't return anything (thus why you get None).
import random
words = ['red', 'adventure', 'cat', 'cat']
random.shuffle(words)
print(words) # Possible Output: ['cat', 'cat', 'red', 'adventure']
Edit:
Given your edit, what you need to change is:
from random import shuffle
words = ['red', 'adventure', 'cat', 'cat']
newwords = words[:] # Copy words
shuffle(newwords) # Shuffle newwords
print(newwords) # Possible Output: ['cat', 'cat', 'red', 'adventure']
or
from random import sample
words = ['red', 'adventure', 'cat', 'cat']
newwords = sample(words, len(words)) # Copy and shuffle
print(newwords) # Possible Output: ['cat', 'cat', 'red', 'adventure']
random.shuffle() is a method that does not have a return value. So when you assign it to a identifier (a variable, like x) it returns 'none'.