请问这个是python的BUG吗？

# -*- coding: utf-8 -*-
globalChar=[['0','0']]*2
print 'globalChar',globalChar
globalChar[1][1]='1'#使左
print 'globalChar',globalChar

得到的输出：

globalChar [['0', '0'], ['0', '0']]
globalChar [['0', '1'], ['0', '1']]

globalChar=[['0','0'],['0','0']]
print 'globalChar',globalChar
globalChar[1][1]='1'#使左
print 'globalChar',globalChar

globalChar [['0', '0'], ['0', '0']]
globalChar [['0', '0'], ['0', '1']]

如果不算BUG的话这也是一个过于隐晦的用法吧，耽误了我不少时间。