'Mount a new app from a root object, script_name, and config.
root
An instance of a "controller class" (a collection of page
handler methods) which represents the root of the application.
This may also be an Application instance, or None if using
a dispatcher other than the default.
script_name
A string containing the "mount point" of the application.
This should start with a slash, and be the path portion of the
URL at which to mount the given root. For example, if root.index()
will handle requests to "http://www.example.com:8080/dept/app1/",
then the script_name argument would be "/dept/app1".
It MUST NOT end in a slash. If the script_name refers to the
root of the URI, it MUST be an empty string (not "/").
config
A file or dict containing application config.'

def mount(self, root, script_name='', config=None):

    if (script_name is None):
        raise TypeError("The    'script_name'    argument    may    not    be    None.    Application    objects    may,    however,    possess    a    script_name    of    None    (in    order    to    inpect    the    WSGI    environ    for    SCRIPT_NAME    upon    each    request).    You    cannot    mount    such    Applications    on    this    Tree;    you    must    pass    them    to    a    WSGI    server    interface    directly.")
    script_name = script_name.rstrip('/')
    if isinstance(root, Application):
        app = root
        if ((script_name != '') and (script_name != app.script_name)):
            raise ValueError('Cannot    specify    a    different    script    name    and    pass    an    Application    instance    to    cherrypy.mount')
        script_name = app.script_name
    else:
        app = Application(root, script_name)
        if ((script_name == '') and (root is not None) and (not hasattr(root, 'favicon_ico'))):
            favicon = os.path.join(os.getcwd(), os.path.dirname(__file__), 'favicon.ico')
            root.favicon_ico = tools.staticfile.handler(favicon)
    if config:
        app.merge(config)
    self.apps[script_name] = app
    return app
