I don't know what i'm doing wrong here. I don't know if the indentation or syntax is the problem.
n = [[1, 2, 3], [4, 5, 6, 7, 8, 9]] # Add your function here def flatten(lists): results =  for l in lists: for i in num: results.append(i) return results print flatten(n)
Traceback (most recent call last): File "python", line 9, in <module> File "python", line 6, in flatten NameError: global name 'num' is not defined
num already defined though? My code has
num as a number in an inner