input: Write a function to calculate the sum of squares of all numbers provided in the given array of integers. If the array is empty, return 0 as the sum of squares.
  
  assert sum_squares([2, 3, 4]) == 29
  assert sum_squares([1, 2, 3, 4, 5]) == 55
  assert sum_squares([]) == 0
  assert sum_squares([0]) == 0
  assert sum_squares([-1, -2, -3]) == 14
output: def sum_squares(arr):
      return sum(x**2 for x in arr)