How to set torn off window's size?

Greetings,

I tore off a new window with:

bpy.ops.screen.area_dupli('INVOKE_DEFAULT')

I would like to change its position and size, however seem to be unable to find out how.

In an old version there was “GetScreenSize()” => https://docs.blender.org/api/2.49/
However, this is not present anymore…
Do I need to use the win32gui Python extension? Could somebody maybe link me to a tutorial on how to use non Blender native

This may be more of a window-manager issue and not something I would expect blender to handle.