input: Write a python function to calculate the sum of squared numbers from start to end.
  assert sum_of_squares(1, 10) == 385
  assert sum_of_squares(0, 0) == 0
  assert sum_of_squares(3, 5) == 50
output: def sum_of_squares(start, end):
      return sum(i**2 for i in range(start, end + 1))