input: Write a function to calculate the cubic values of a list of numbers ranging from 1 to 8 and print each result. The function should take a list as input and return None.
  assert print_cubes([1, 2, 3, 4, 5, 6, 7, 8])==None
  assert print_cubes([1, 2, 3, 4, 5, 6, 7, 8])==None
  assert print_cubes([1, 2, 3, 4, 5, 6, 7, 8])==None
  assert print_cubes([1, 2, 3, 4, 5, 6, 7, 8])==None
  assert print_cubes([1, 2, 3, 4, 5, 6, 7, 8])==None
output: def print_cubes(numbers):
      for num in numbers:
          print(num ** 3)
      return None