input: Write a function that takes a list of numbers ranging from 1 to 8 and prints their cubic values. Handle empty lists by returning immediately.
  
  assert print_cubics([1, 2, 3, 4, 5, 6, 7, 8])==None # should print 1, 8, 27, 64, 125, 216, 343, 512
  assert print_cubics([])==None # should print nothing and return immediately
  assert print_cubics([3, 6, 1])==None # should print 27, 216, 1 and return immediately
output: def print_cubics(numbers):
      if not numbers:
          return
      for num in numbers:
          print(num ** 3)