Sometimes a copy is required so that you can change one copy without changing another. Python has two ways of making copies:
To make these copies, we use copy module. We use the copy module for shallow and deep copy operations. For example
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In the above code, copy () returns a shallow copy of the list, and deepcopy () returns a deep copy of the list.
Deep Copy — it is a process in which the copying process occurs recursively. This means first creating a new collection object and then recursively filling it with copies of the child objects found in the original. In the case of a deep copy, a copy of an object is copied to another object. This means that any changes made to the copy of the object are not reflected in the original object. In python this is done using the deepcopy () function.
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Exit:
The original elements before deep copying 1 2 [3, 5] 4 The new list of elements after deep copying 1 2 [7, 5] 4 The original elements after deep copying 1 2 [3, 5] 4
In the above example, a change made to the list did not affect other lists, indicating deep copying list.
Shallow copy means creating a new collection object and then populating it with references to child objects found in the original. The copying process does not repeat itself and therefore does not create copies of the child objects themselves. In the case of a shallow copy, a reference to an object is copied to another object. This means that any changes made to the copy of the object are reflected in the original object. Python does this with the " copy () " function.
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Exit:
The o riginal elements before shallow copying 1 2 [3, 5] 4 The original elements after shallow copying 1 2 [7, 5] 4
In the above example, the change made to the list is took effect on another list, indicating that the list was copied.
Important points:
The difference between shallow and deep copies only applies to composite objects (objects that contain other objects, such as lists or class instances):
