Scripting window position

[rcampos devel gmail com]

Hello,

Is it possible to modify a window's position from an external program
such as a python script?

For example, I would like a script to move my current Firefox window to
the left bottom corner of the Desktop and have a size of 400x400.

I'm not sure if this is going in the right direction, but I found the
GTK library has functions to get and set window positions, but I'm not
sure how to specify the particular window instance, such as the Firefoxwindow in the example above.  

Any help would be greatly appreciated.

-Renan C.