Any reason why you're using a slice here? >>> numbers[:] = [n for n in numbers if not odd(n)] I'm thinking that doing >>> numbers = [n for n in numbers if not

Any reason why you're using a slice here? >>> numbers[:] = [n for n in numbers if not odd(n)] I'm thinking that doing >>> numbers = [n for n in numbers if not odd(n)] wouldn't be a problem since the assignment is executed after the computation of the list comprehension.