201_16_property_setter_decorator.py

# we will discuss three problems in existing 
# then we will solve them using getter, setter decorator


class Phone:
    def __init__(self, brand, model_name, price):
        self.brand = brand
        self.model_name = model_name
        self._price = max(price,0)   
        # self.complete_specification = f"{self.brand} {self.model_name} and price is {self._price}"

    @property          # when property decorater used you can used as a instance
    def complete_specification(self):
        return f"{self.brand} {self.model_name} and price is {self._price}"

    # getter # setter
    @property
    def price(self):
        return self._price
    @price.setter
    def price(self, new_price):
        self._price = max(new_price,0)

    def make_a_call(self, phone_number):
        print(f"calling {phone_number} ...")
 
    def full_name(self):
        return f"{self.brand} {self.model_name}"


phone1 = Phone('nokia', '1100', 1000)
print(phone1._price)
print(phone1.complete_specification)    # couse used property decorator

phone1._price = -500
print(phone1._price)
# print(phone1.complete_specification())
print(phone1.complete_specification)    # couse used property decorator

phone1.price = -500           # this is only a better version of '_price'
print(phone1.price)
# print(phone1.complete_specification())
print(phone1.complete_specification)    # couse used property decorator