input: Write a function to print the first 10 cubes of natural numbers. If the input is None or empty, it should not print anything.
  assert first_10_cubes(None)
  assert first_10_cubes("")
  assert first_10_cubes()
output: def first_10_cubes(input_str=None):
      if input_str is None or input_str == "":
          return
      for i in range(1, 11):
          print(i ** 3)