Copy and deepcopy, pythondeepcopy

Copy and deepcopy, pythondeepcopy

1. Normal assignment copy:

It can be found that B and a have the same id,

When a changes, B changes accordingly.

2. Shallow copy:

 

At this time, the two IDs are different. When the shortest copy occurs, the original data sub-object a [2] changes, and c changes, but the original data changes. The copy object does not. That is, the child object of the original data is copied.

3. Deep copy deepcopy:

In the same way, the two IDs are different. Deep copy is a copy of the original data object. That is, no matter how the original data changes, the copied data will not change.