Question: 
Write a function to calculate the sum of series 1²+2²+3²+….+n².


Model's Code:
def series_sum(n):
    return sum(i**2 for i in range(1, n + 1))



Sample Correct Code:
def series_sum(number):
 total = 0
 total = (number * (number + 1) * (2 * number + 1)) / 6
 return total


Asserts:
assert series_sum(6)==91
assert series_sum(7)==140
assert series_sum(12)==650


Tests:
Test 1 of 3: PASS
Test 2 of 3: PASS
Test 3 of 3: PASS

Test 935 of 974: 717/935 (76.68449197860963%): success