Mean Square Error

DESCRIPTION:

Complete the function that

• accepts two integer arrays of equal length
• compares the value each member in one array to the corresponding member in the other
• squares the absolute value difference between those two values
• and returns the average of those squared absolute value difference between each member pair.

Examples

[1, 2, 3], [4, 5, 6]              -->   9   because (9 + 9 + 9) / 3
[10, 20, 10, 2], [10, 25, 5, -2]  -->  16.5 because (0 + 25 + 25 + 16) / 4
[-1, 0], [0, -1]                  -->   1   because (1 + 1) / 2

---

def solution(aa, bb):
    alist=[]
    for i in range(len(aa)):
        alist.append((aa[i]-bb[i])*(aa[i]-bb[i]))
    return (sum(alist)/len(aa))