Shallow vs Deep Copy: copy.copy and copy.deepcopy

Why does `copy.copy` leave your sublists shared, and when do you actually need `copy.deepcopy`?

Finger exercises

Short drills on what this video just taught. Write the code, run the checks, and reveal the answer only if you are stuck.

0 / 5 passed

Exercise 1 of 5

One object, two names

old holds three sublists. Make new a second name for that same list object — no copy of any kind. Then, working only through new, change the element at position 1 of the third sublist to 6, and append the sublist [7, 8].

# Alias old, then mutate it through the second name only.
old = [[1, 2], [3, 4], [5, "foo"]]

# your code here

# Alias old, then mutate it through the second name only.
old = [[1, 2], [3, 4], [5, "foo"]]

# your code here

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⌘/Ctrl + Enter runs

`new` is a second name for the same object

the third sublist was edited in place

`old` sees every change made through `new`

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