Reimport a module while interactive

The 411 about reload()

Syncing Module Changes

If you're a proud Pythonista tweaking your module's source code but wondering why the changes are not reflecting in the interactive session — importlib.reload() is your buddy. It updates the module with the latest changes.

# After your ninja edits to 'my_module.py'
import importlib.reload
reload(my_module) # There you go!
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Preserving Original Objects

Your existing objects from the module before the reload will stick around with their state and identity intact. So, if you've got an instance named my_instance of my_module.MyClass, it will still be there after the reload, albeit linked to the old class definition.

my_instance = my_module.MyClass() # Created a MyClass instance
reload(my_module) 
# 'my_instance' says, "Why you reload without me?"
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Imports: Direct vs. From

To effectively use the reload, stick with direct imports (e.g., import my_module) instead of from my_module import .... When you use direct imports, the reloaded module's namespace is updated. However, with the latter syntax, the loaded symbols might not reflect the updates.

Alias: A matter of identity

If you've got an alias for your module during import (like how pythonistas prefer their Starbuck names), ensure to use the same alias during reload:

import my_module as mm # my_module alias mm checks-in
reload(mm) # mm says, "Hey, I'm mm, not my_module. Remember me?"
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Handy Tips and Tricks for Real Pythonistas

Automagic Reloading with IPython

IPython's autoreload extension can auto-refresh your module, allowing you to keep the development flowing without manual reloads:

%load_ext autoreload
%autoreload 2 # With this, Python plays by the "change is constant" rule.
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Deprecated imp — A Tale of Forgotten Relic

Once upon a time in Python 3.2 and 3.3, imp.reload() was a thing. Now, it's a deprecated tech relic. Today's hip method is importlib.reload().

Version-specific Plot Twist

In the Python cinematic universe, reload() was a built-in function in Python 2.x. However, in Python 3.x, reload() lost its built-in status. Now, it bravely lives on as importlib.reload().

Seamless Workflow

Maintain the continuity of your workflow by using importlib.reload() to update your modules without needing a session restart. It reflects .py file edits instantly, allowing you to focus on coding without disruptions.