[DecoratorPattern]wikiのサンプルコードをpython3実装

wikiのdecoratorのサンプルコードをpython3.xで実装したコードです。(環境python3.9)
Decorator パターン

元がjavaのため、@propertyは使わず、そのままゲッターで実装しています。

decorator_pattern.py

"""UML
                        << Component >>
                        operation()  < -----------------
                        |       |                      |
    Concrete Component          Decorator(Component) :use Component
    operation()                 |
                                Concrete Decorator (Decorator)
                                operation()


    deco = ConcreteDecorator_A(
                ConcreteDecorator_B(
                    ConcreteComponent()
                )
            )
    deco.operation()
"""

from abc import ABC, abstractmethod


# Component
class Price(ABC):

    @abstractmethod
    def get_value(self) -> int:
        pass

# Concrete Component
class PrimePrice(Price):

    def __init__(self, value: int) -> None:
        self.__value = value

    def get_value(self) -> int:
        return self.__value

# Decorator
class MarginPrice(Price):

    def __init__(self, price: Price):
        self._price = price

# Concrete Decorator
class WholeSalePrice(MarginPrice):

    def __init__(self, price: Price, advantage: int):
        super(WholeSalePrice, self).__init__(price)
        self.__advantage = advantage

    def get_value(self) -> int:
        return self._price.get_value() + self.__advantage

# Concrete Decorator 2
class DoublePrice(MarginPrice):

    def get_value(self) -> int:
        return self._price.get_value() * 2



if __name__ == '__main__':

    prime_price = PrimePrice(100)
    print(prime_price.get_value())

    whole_sale_price = WholeSalePrice(prime_price, 50)
    print((whole_sale_price.get_value()))

    # double_sale_price = DoublePrice(prime_price)
    double_sale_price = DoublePrice(whole_sale_price)
    print(double_sale_price.get_value())