class Person:
    eyes = 2
    nose = 1
    mouth = 1
    ears = 2
    arms = 2
    legs = 2

    def eat(self):
        print('얌냠...')

    def sleep(self):
        print('쿨쿨...')

    def talk(self):
        print('주절주절...')

class Singer:                    
     def sing(self):             
        return "butter"

bts = Singer()                   
bts.sing()      