'Dispatch the request to the appropriate controller.
Called by self._router after matching the incoming request to a route
and putting the information into req.environ.  Either returns 404
or the routed WSGI app\'s response.'

@staticmethod
@webob.dec.wsgify(RequestClass=request_mod.Request)
def _dispatch(req):

    match = req.environ['wsgiorg.routing_args'][1]
    if (not match):
        msg = (_('(%(url)s):    The    resource    could    not    be    found.') % {'url': req.url})
        return render_exception(exception.NotFound(msg), request=req, user_locale=best_match_language(req))
    app = match['controller']
    return app
