Deep Copies

The copy Module How Deep Copy Works When to Use Each Copy Choose shallow copy when your list contains only immutable objects (numbers, strings) or when you do not intend to modify nested structures. Choose deep copy when your list contains mutable objects that you might modify. The Multiplication Trap The code below creates a grid using the multiplication trap. Fix it so that modifying one row does not affect the others. The choice between shallow and deep copy is a performance trade-off. For large structures with many levels of nesting, deep copy can be slow. Profile your code if copy performance becomes a bottleneck.

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