decorator_cached_property.py

from cached_property import cached_property

class Monopoly(object):

    def __init__(self):
        self.boardwalk_price = 500

    @cached_property
    def boardwalk(self):
        # using example from cached_property pypi document
        # no matter times you calling this method, it's just execute once
        # so, print just once and price just add once
        print("======hello world======")
        self.boardwalk_price += 50
        return self.boardwalk_price

monopoly = Monopoly()
print(monopoly.boardwalk)
print(monopoly.boardwalk)