This example comments out a selection in Microsoft Developer Studio.
import win32com.client
# This script comments out the currently selected text block
app = win32com.client.Dispatch('MSDev.Application')
wnd = app.ActiveWindow
if wnd.Type == 'Text':
# Get current selection
select = str(wnd.Selection)
# comment out
s = map(lambda x:'//'+x,select.split('\r\n'))
# Replace current selection by new textbuffer
wnd.Selection = '\r\n'.join(s)
app = None