Slight nitpick: >> The list comprehension starts with a '[' and ']', to help you remember that the result is going to be a list. You wrap that in [] because y

Slight nitpick: >> The list comprehension starts with a '[' and ']', to help you remember that the result is going to be a list. You wrap that in [] because you are creating a list. If you use () instead, you are creating a generator object.