new_contents: class wolf(object): 
      def bark(self):
          print "hooooowll"
  
  class dog(object): 
      def bark(self):
          print "woof"
  
  
  def barkforme(dogtype):
      dogtype.bark()
  
  
  my_dog = dog()
  my_wolf = wolf()
  barkforme(my_dog)
  barkforme(my_wolf)
  
subject: Create poly_morp.py