virtual host in cherrypy 3.2 / python 3

#!/usr/bin/env python

import cherrypy
from cherrypy import expose

class Root(object):

    @expose
    def index(self):
        return "I am the root  vhost"
    index.exposed = True

class Foo(object):

    @expose
    def index(self):
        return "I am testingdomain.com"
    index.exposed = True

class Bar(object):

    @expose
    def index(self):
        return "I am testingdomain2.com."
    index.exposed = True

def main():

    #cherrypy.config.update("conf.ini")

    cherrypy.config.update({'server.socket_host': 'rootdomain.com',
            'server.socket_port': 80,
    })

    conf = {
        "/": {
            "request.dispatch": cherrypy.dispatch.VirtualHost(
            **{
                "testingdomain.com:8000": "/foo",
                "testingdomain2.com:8000": "/bar"
            })
        }
    }

    root = Root()
    root.foo = Foo()
    root.bar = Bar()
    cherrypy.tree.mount(root, "/", conf)

    #cherrypy.quickstart()
    cherrypy.engine.start()
    cherrypy.engine.block()

if __name__ == "__main__":
    main()