class Enemy:
   life = 3
   
   def attack(self):
       print('attack!')
       self.life -= 1


   def checkLife(self):
       if self.life <= 0:
           print("I am dead")
       else:
           print(str(self.life) + " life left")



enemy1 = Enemy()
enemy2 = Enemy()


# each object is independent of one another, they don't share variables
enemy1.attack()
enemy1.attack()
enemy1.checkLife()
enemy2.checkLife()