I have used following code in utils.py of stock module

def urlopen():
	import webbrowser
        webbrowser.open_new("http://localhost:8200/201307091452.png")
        return "hi"

and i am calling this fun on_update of item

def on_update(self):
		import datetime
		from datetime import date
                from stock.utils import urlopen
                ww=urlopen()