Python bug?

Python 2.5.2 (r252:60911, Sep 11 2008, 13:43:31) 
[GCC 4.2.4] on linux2
>>> a = [[False] * 2] * 2
>>> a[0][0] = True
>>> a[1][0]
True

Well, maybe not a bug, but definitely a pitfall that should be avoided during coding.

- Written on Tue Feb 24 21:51:59 2009.