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| == Usage == === Copy === Make a shallow copy of an object with `copy()`. === DeepCopy === Make a '''deep copy''' of an object with `deepcopy()`. |
== Concept == |
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| The `deepcopy()` solution involves: | Creating a deep copy then involves: |
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---- == Usage == === Copy === Make a shallow copy of an object. === DeepCopy === Make a deep copy of an object. |
Python Copy
copy is a module for deep- and shallow-copying operations.
Concept
A deep copy differs from a shallow copy only for containers. A shallow copy contains references to the same objects that the original contains. A deep copy contains copies of the original's contents.
This poses two challenges:
- Recursive objects may contain a reference to themselves, and causing a recursion loop
- Some data should be copied once and shared among the contents
Creating a deep copy then involves:
Allowing objects to override the operation to avoid loops; see __deepcopy__ for details
Keeping a memo dictionary for data already copied, so that it can be shared among the contents
Usage
Copy
Make a shallow copy of an object.
DeepCopy
Make a deep copy of an object.
See also
Python copy module documentation