input: Write a function to take a list of numbers from 1 to 8 and print each number's cubic value. 
  
  assert cube_values([1, 2, 3, 4, 5, 6, 7, 8])
  
  # The expected output is the printed cubic values of each number in the list.
output: def cube_values(numbers):
      for num in numbers:
          print(num ** 3)