Do I have to reload a module in python to capture changes?

Question

I am running python 3.6.4 (anaconda, spyder).

Do I need to reload a user-defined module in order to capture the changes?

For example, suppose I wrote the simple function and save it in test.py file:

def plus5(x):
    return x + 5

Then in the IPython console I type

import test as t

and then I change the user-defined function to:

def plus5(x):
    return x + 500

Then when I type in IPython console

t.plus5(0)

it returns 500 without re-importing or reloading the module first.

If I change the function name from plus5 to something else then I have to re-import the module to see the change. But when I change the function statements then it automatically captures the changes without re-importing the module

From the Python documentation:

Note: For efficiency reasons, each module is only imported once per interpreter session. Therefore, if you change your modules, you must restart the interpreter – or, if it’s just one module you want to test interactively, use importlib.reload()

e.g. import importlib; importlib.reload(modulename).

Answer 1

This is a feature in the IPython interpreter name autoreload. It has the magic command %autoreload which allows for activating or deactivating this feature. It seems to be on by default, but I was not able to find something proving that.