slice - Python : Why use "list[:]" when "list" refers to same thing? -

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consider list >>> l=[1,2,3].

what benefit of using >>> l[:] when >>> l prints same thing former does?

thanks.

it creates (shallow) copy.

>>> l = [1,2,3] >>> m = l[:] >>> n = l >>> l.append(4) >>> m [1, 2, 3] >>> n [1, 2, 3, 4] >>> n l true >>> m l false

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