`copy`

The Python copy module provides functionality to create shallow copy and deep copies of objects in Python.

This module is useful when you need to duplicate objects while ensuring that the original and the copy can be modified independently.

Here’s a quick example:

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>>> import copy

>>> original = [1, 2, [3, 4]]
>>> duplicate = copy.deepcopy(original)
>>> duplicate[2][0] = "changed"

>>> original
[1, 2, [3, 4]]
>>> duplicate
[1, 2, ['changed', 4]]

Key Features

Creates shallow copies of objects
Creates deep copies of objects
Ensures independent modification of copies from originals

Frequently Used Classes and Functions

Object	Type	Description
`copy.copy()`	Function	Creates a shallow copy of an object
`copy.deepcopy()`	Function	Creates a deep copy of an object

Examples

Creating a shallow copy of a list:

Python
      
>>> original = [1, 2, 3]
>>> shallow_copy = copy.copy(original)
>>> shallow_copy is original
False

Creating a deep copy of a nested list:

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>>> original = [1, 2, [3, 4]]
>>> deep_copy = copy.deepcopy(original)
>>> deep_copy[2][0] = "changed"
>>> original
[1, 2, [3, 4]]

Common Use Cases

Duplicating complex objects without shared references
Ensuring that modifications to copies don’t affect the original object
Creating backup states of objects for undo functionality

Real-World Example

Suppose you’re working on a project where you need to maintain versions of a configuration dictionary. You can use the copy module to create deep copies of the configuration at different states:

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>>> import copy

>>> config = {"dark": True, "coordinates": [1, 2, 3]}
>>> config_user = copy.deepcopy(config)
>>> config_user["coordinates"][2] = 4
>>> config
{'dark': True, 'coordinates': [1, 2, 3]}

>>> config_user
{'dark': True, 'coordinates': [1, 2, 4]}

By using copy.deepcopy(), you ensure that modifications to config_user don’t affect config, allowing for independent version management.

Shallow vs Deep Copying of Python Objects

Tutorial

How to Copy Objects in Python: Shallow vs Deep Copy Explained

Understand the difference between shallow and deep copies in Python. Learn how to duplicate objects safely using the copy module and other techniques.

advanced python

For additional information on related topics, take a look at the following resources: