Python 3.6:
>>> x = [0, 1]
>>> y = [[]]*2
>>> z = dict(zip(x, y))
>>> z
{0: [], 1: []}
>>> z[0].append(0)
>>> z
{0: [0], 1: [0]}
>>>
Why did it append to both? I tried without zip and it worked fine. Please explain this behavior
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jwodder
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Peri Javia
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3Short version, `*2` copies the references, doesn't know about calling constructors. – Mad Physicist Mar 22 '18 at 16:21
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https://stackoverflow.com/questions/6688223/python-list-multiplication-3-makes-3-lists-which-mirror-each-other-when – Dariusz Krynicki Mar 22 '18 at 16:25