How to Create Independent Copies of Objects in Python?

Copying Objects in Python: Independent Instances

Problem Statement:

In Python, creating a copy of an object may seem as simple as assigning one object to another. However, this simple assignment creates a reference to the original object instead of a new independent instance.Modifications to one object will propagate to the other.This can lead to unexpected behavior and potential bugs.

Solution: Deep Copying with copy.deepcopy()

To create a genuinely independent copy of an object, we employ the copy.deepcopy() function from the copy module. This function performs a deep copy, recursively copying all attributes and child objects of the original object.The resulting copy is an independent object with its own memory location and values.

Example:

<code class="python">import copy

original_obj = {'name': 'Alice', 'age': 30}
copy_obj = copy.deepcopy(original_obj)

copy_obj['name'] = 'Bob'  # Modify copy

print(original_obj)  # Output: {'name': 'Alice', 'age': 30} (Unchanged)
print(copy_obj)  # Output: {'name': 'Bob', 'age': 30} (Independent)</code>

In this case, copy_obj is genuinely independent from original_obj. Modifying one does not affect the other.This enables you to create multiple objects with distinct values while sharing the same initial properties.

Note:

Shallow copying, which can be achieved with copy.copy(), only copies the data structure's values,leaving any contained references as they were.Deep copying is generally preferred to ensure object independence.

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