any one can answer this basic python quesion?

Question 2: Sum of a Series (4 points) The value of (12 + 22 + + Yn3 is always greater than 1 /3 for any n 1 and as n grows, the value gets closer to 1/3. Write a Python function onethird (n) that returns a floating-point number according to this formula. In : def onethird(n): # Your code here return s