Wrapping around a list in Python.

[shengjie.shengjie at live.com]

Hi guys, I am trying to create a fixed list which would allow my values to be wrapped around it.
For example i have 10 values : 0,1,2,3,4,5,6,7,8,9
I need to create a list which contains 4 numbers and when the number exceeds the list, it would overwrite the first value.
[0,1,2,3]
[4,1,2,3]
[5,4,1,2]

Thanks in advance and much help appreciated.