在Python中记住静态属性

Memoizing static properties in Python

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我有两个类，其中一个类设置起来很昂贵，但可以重用，另一个类在我的应用程序中有许多实例，但可以重用昂贵类的实例。这很容易用例子来解释：

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class SomeExpensiveToSetUpClass(object):
def __init__(self):
print("Expensive to set up class initialized")
self.whatever ="Hello"

def do_the_thing(self):
print(self.whatever)

class OftenUsedClass(object):

@staticmethod
@property
def expensive_property():
try:
return OftenUsedClass._expensive_property
except AttributeError:
OftenUsedClass._expensive_property = SomeExpensiveToSetUpClass()
return OftenUsedClass._expensive_property

# I know I could hide the static property in an instance property:
@property
def expensive_property2(self):
try:
return OftenUsedClass._expensive_property
except AttributeError:
OftenUsedClass._expensive_property = SomeExpensiveToSetUpClass()
return OftenUsedClass._expensive_property
#
# And then:
#
# ouc = OftenUsedClass()
# ouc.expensive_property2.do_the_thing()
# ouc.expensive_property2.do_the_thing()
# ouc.expensive_property2.do_the_thing()
#
# but that feels misleading

if __name__ == '__main__':
OftenUsedClass.expensive_property.do_the_thing()
OftenUsedClass.expensive_property.do_the_thing()
OftenUsedClass.expensive_property.do_the_thing()

正如你所看到的，我希望我可以使用@staticmethod和@property在第一次使用该属性时基本上记忆该属性，但没有骰子——我将得到property的实例：

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Traceback (most recent call last):
File"memo.py", line 39, in <module>
OftenUsedClass.expensive_property.do_the_thing()
AttributeError: 'property' object has no attribute 'do_the_thing'

我发现了几种用于记忆装饰的模式，但没有用于静态属性。我错过什么了吗？或者我应该使用另一种模式？

编辑：

我过于简单化了我的问题：我应该将SomeExpensiveToSetUpClass类实现的名称包含在配置文件中，所以直到第一次实例化OftenUsedClass时我才知道它的名称。