This isn\'t as malicious as it sounds, I want to get the current size of their windows, not look at what is in them. The purpose is to figure out that if every other window
I'm a big fan of AutoIt. They have a COM version which allows you to use most of their functions from Python.
import win32com.client
oAutoItX = win32com.client.Dispatch( "AutoItX3.Control" )
oAutoItX.Opt("WinTitleMatchMode", 2) #Match text anywhere in a window title
width = oAutoItX.WinGetClientSizeWidth("Firefox")
height = oAutoItX.WinGetClientSizeHeight("Firefox")
print width, height