在Python中重新加载内置函数

Question

我正在探索Python中名称空间的概念，我无法解释以下问题：重新加载builtins不能有效地重新加载模块。下面是一个例子：

import importlib as il
import os

import mymodule
mymodule.x = 6
print(mymodule.x)
mymodule = il.reload(mymodule)
print(mymodule.x)


import builtins
builtins.print = lambda x : os.system('echo hello')
builtins.print('hi')
builtins = il.reload(builtins)
builtins.print('hi')

其中mymodule只包含赋值x = 5。输出为：

^{pr2}$

也许这是个愚蠢的问题，但为什么会有这种行为呢？在

Answer 1

从docs：

It is generally not very useful to reload built-in or dynamically loaded modules. Reloading sys, __main__, builtins and other key modules is not recommended. In many cases extension modules are not designed to be initialized more than once, and may fail in arbitrary ways when reloaded.