input: Write a python function to convert a list into a 2D array.
  assert convert_list_to_2d_array(["a", "b", "c", "d", "e", "f", "g", "h", "i"]) == [['a', 'b', 'c'], ['d', 'e', 'f'], ['g', 'h', 'i']]
  assert convert_list_to_2d_array([1, 2, 3, 4, 5, 6, 7, 8, 9]) == [[1, 2, 3], [4, 5, 6], [7, 8, 9]]
  assert convert_list_to_2d_array([1, 2, 3, 4]) == [[1, 2], [3, 4]]
output: def convert_list_to_2d_array(lst):
      n = int(len(lst) ** 0.5)
      return [lst[i * n:(i + 1) * n] for i in range((len(lst) + n - 1) // n)]