input: Write a python function to find the maximum value in a 3D array.
  assert calc_max([[[1, 2, 3], [4, 5, 6]], [[7, 8, 9], [10, 11, 12]]]) == 12
  assert calc_max([[[5, 17], [23, 1]], [[-1, -5], [0, 3]]]) == 23
  assert calc_max([[[0, 0, 0], [0, 0, 0]], [[0, 0, 0], [0, 0, 0]]]) == 0
output: def calc_max(array):
      max_value = float('-inf')
      for layer in array:
          for row in layer:
              for item in row:
                  if item > max_value:
                      max_value = item
      return max_value