Does [:] slice only make shallow copy of a list?

Question

I have experienced peculiar bugs from this [:] copy.

The docs say [:] makes only a shallow copy but seems:

a = [1,2,3]
id(         


        

Answer 1

The difference is that the elements of list a and list b are the same. Changing mutable objects in either list also effects the elements in the other list.

In contrast there is deepcopy which tries to create a completely different set of objects.