class Animal:
    def __init__(self):
        print "Animal initialized"
        
    def eat(self):
        print "Ate something"
    
    
class Mammal(Animal):
    def __init__(self):
        Animal.__init__(self)
        print "Mammal initialized"
        
    def live_young(self):
        print "Bore live young"
        
        
class Fish(Animal):
    def __init__(self):
        Animal.__init__(self)
        print "Fish initialized"
        
    def swim(self):
        print "Swam around"
        
    def lay_eggs(self):
        print "Laid eggs"
        
        
class Whale(Mammal, Fish):
    def lay_eggs(self):
        raise Exception("Whales are mammals and can't lay eggs")