def mydecor(func):
    def wrapper():
        print('before')
        func()
        print('after')
    return wrapper()

@mydecor
def main():
    print('salam')

main()

class person:
    def __init__(self , name , family , age):
        self.name = name
        self.family = family
        self.age = age
    def showfullname(self):
        return f'name = {self.name} ' \
               f'family = {self.family}' \
               f'age = {self.age}'
    def __repr__(self):
        return f'name = {self.name} '\
               f'family = {self.family}'\
               f'age = {self.age}'

class user(person):
    pass

me=person('matin' , 'kalamipour' , 19)
you = user('matin' , 'kalamipour' , 19)

class user:
    def __init__(self, name , age):
        self.name = name
        if age>0:
            self._age=age
        else:
            self._age=0


    def get_age(self):
        return self._age

    def set_age(self , valueAge):
        if valueAge>=0:
            self._age=valueAge

class user:
    def __init__(self , age):
        if age >=0:
            self._age = age
        else:
            self._age = 0

    @property
    def age(self):
        return self._age

    @age.setter
    def age(self , value):
        if value >=0:
            self._age = value
        else:
            raise ValueError('invalid value')

me = user(20)
print(me.age)
me.age = 40
print(me.age)

class person:
    def __init__(self,name , family):
        self.name = name
        self.family = family

    @property
    def fullname(self):
        return f'{self.name} {self.family}'

class user(person):
    def __init__(self , name , family , age):
        super().__init__(name , family)
        self.age = age


me=user('matin' , 'kalamipour' , 20)
print(me.fullname)