About last 2 blocks in Week9/point_copy.py about ceng2002

[pembeci]

By "they should be same" do you mean W's should be same in rect3 and rect4 output? If you are confused as such, it is just that update statements are different in code:

     rect3.border_width = 9    # W:9
     rect4.border_width = 11   # W:11

If you mean you were expecting rect1 and rect4 output to be same in terms of W at the deep copy part then it means you didn't understand what deep copy is doing. Please clarify, if your confusion was smt else.

[senolakkas]

At the last block, if "rect4 = deepcopy(rect1)" is deepcopy it has to do same work with "rect2 = rect1".

Output of rect2 = rect1 is:
rect1=A green with TP:(0,20,0) BR:(7,0,0) W:7)
rect2=A green with TP:(0,20,0) BR:(7,0,0) W:7)

Output of rect4 = deepcopy(rect1) is:
rect1=A green with TP:(0,40,0) BR:(7,0,0) W:7)
rect4=A pink with TP:(0,60,0) BR:(7,0,0) W:11)

If second one is a deepcopy why rect1 doesn't change when we modify rect4. We thought that there's a reference copy so that rect1 has to change with rect4.

[senolakkas]

As we understand we cannot deep copy objects in deepcopy method, just copy classes and modules.

[pembeci]

rect4 = rect1 creates a reference (alias) to rect1 so updates to rect4 is actually updates to rect1. If you don't want this behavior -i.e. want to change rect4without changing rect1- then you need to clone the object. That's what deepcopydoes in Python. So modifying rect4 doesn't modify rect1 even for references in rect1 like top_left_point since that point is also cloned while creating rect4.