References vs copies w/ *x

[Duncan Booth]

emile at fenx.com (Emile van Sebille) wrote in 
<tl1J3.1900$r8.63155 at news.direcpc.com>:

>>>> a = [1,2,3]
>>>> b = [[]]*3
>>>> b = map(lambda x:a[:],b)
>>>> b[1][1] = 'c'
>>>> b
>[[1, 2, 3], [1, 'c', 3], [1, 2, 3]]
>
>

How about a slightly simpler variant:
>>> a = [1, 2, 3]
>>> b = map(list, [a]*3)
>>> b[1][1] = 'c'
>>> b
[[1, 2, 3], [1, 'c', 3], [1, 2, 3]]

or you can import copy and use copy.copy in the map, but using list avoids 
the import.