input: Write a function to take a list of numbers from 1 to 8 and print their cubic values. If the list is empty, print "No numbers provided".
  assert cubic_values([1, 2, 3, 4, 5, 6, 7, 8])==None
  assert cubic_values([])==None
output: def cubic_values(numbers):
      if not numbers:
          print("No numbers provided")
      else:
          for num in numbers:
              print(num ** 3)