如何改变 yielded value值

以下代码使用上下文管理器将变量存储并加载到文件中。但是，必须设置valuecontext manager（loaded.value）所产生的属性非常烦人。我想要

不必定义像这样的新类 LoadedValue
将context manager（loaded）的yielding值设置为保存的值。
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>

注意：这最初发布在CodeReview上，但我决定在此处重新发布它以获得答案，并将其保留在CodeReview上以帮助以其他方式改进代码。