Nested Lists Assignment Problem

[Licheng Fang]

Dennis Lee Bieber wrote:
> On 26 Apr 2006 01:13:20 -0700, "Licheng Fang" <fanglicheng at gmail.com>
> declaimed the following in comp.lang.python:
>
>
> >
> > Could anybody please explain to me why three values were change? I'm
> > bewildered. Thanks!
>
> http://www.aifb.uni-karlsruhe.de/Lehrangebot/Winter2000-01/E-Shop/Python/Doku/The%20Whole%20Python%20FAQ.htm#4.50
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Thank you very much!

But I still wonder why a nested assignment "a = [[0]*3]*3" generates 3
references to the same list, while the commands below apparently do
not.

>>> a = [0] * 2
>>> a
[0, 0]
>>> a[0] = 1
>>> a
[1, 0]