Append function is evaluating the empty list beforehand, how do I get past this ?
I've defined an empty list and append is evaluating it as none prior to appending it
Traceback (most recent call last):
File "python", line 9, in
File "python", line 7, in flatten
AttributeError: 'NoneType' object has no attribute 'append'
It was supposed to append into the list
n = [[1, 2, 3], [4, 5, 6, 7, 8, 9]] # Add your function here def flatten(lists): results =  for numbers in lists: for number in numbers: results = results.append(number) return results print flatten(n)