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In the latest Python (3.2):
>>> l = [{}]*2
>>> l[1]['key'] = 'value'
>>> l
[{'key': 'value'}, {'key': 'value'}]
I expected l to be [{}, {'key': 'value'}] after this operation. Is it normal behaviour or a bug?
Normal. Try using
l = [{} for x in range(2)]instead.[{}]*2does not actually make 2 different dictionaries – it makes a list with two references to the same dictionary. Thus, updating that dictionary makes changes show up for both items in the list, because both items are actually the same dictionary, just referenced twice.