import webbrowser
#select the url you want to open
url = 'http://docs.python.org/'
#set browser path
chrome_path = 'open -a /Applications/Google\ Chrome.app %s'
#open browser, search URL
webbrowser.get(chrome_path).open(url)
Your browser should open after running the above.
Your Chrome path may vary so if you need to debug would start there.