如何改变产出值

以下代码使用上下文管理器将变量存储和加载到文件中。 但是,设置 value 上下文管理器生成的内容的属性( loaded.value ) 我想

1. 不必像这样定义新类 LoadedValue
2. 设置上下文管理器的生成值( loaded )为保存的值。

解决这些问题中的任何一个都会受到赞赏。

import os
import pickle
from contextlib import contextmanager

class LoadedValue:
    def __init__(self, value):
        self.value = value

    def __str__(self):
        return "<LoadedValue: {}>".format(self.value)

@contextmanager
def load_manager(load_file="file.pkl"):
    with open(load_file, "rb") as f:
        loaded_object = LoadedValue(pickle.load(f))
    try:
        yield loaded_object
    finally:
        with open(load_file, "wb+") as f:
            pickle.dump(loaded_object.value, f)

if __name__ == "__main__":
    filename = "test.pkl"
    with open(filename, "wb+") as f:
        pickle.dump(7, f)

    with load_manager(filename) as loaded:
        print(loaded) # >>> <LoadedValue: 7>
        loaded.value = 5 # this is what I have to do
        # loaded = 5  # this is what I want to do

    with load_manager(filename) as loaded:
        print(loaded) # >>> <LoadedValue: 5>

注:这是 originally posted 关于代码审查,但是我决定把它放在这里,以便得到答案,并把它留在代码审查中,以帮助以其他方式改进代码。