Simple list.append() question

[Matthew Hirsch]

Hi All,

I have this:
>>> entire_list=[[]]*3
>>> entire_list
[[], [], []]
>>> entire_list[0].append(1.23)
>>> entire_list
[[1.23], [1.23], [1.23]]

I only want to append 1.23 to entire_list[0].  Why did it also append it 
to entire_list[1] and entire_list[2]?

Thanks for your help,
Matt