how to do draw pattern with python?

[echo.hping at gmail.com]

may i know how to shift the bits using only looping and branching??

x....x
.x..x.
..xx..
..xx..
.x..x.
x....x

xx....
..x..x
...xx.
...xx.
..x..x
xx....

.xx...
x..x..
....xx
....xx
x..x..
.xx...

etc..