def fromOpenIDRequest(cls, request):
        """Instantiate a Request object from the arguments in a
        C{checkid_*} OpenID message
        """
        self = cls()
        args = request.message.getArgs(self.ns_uri)
        is_openid1 = request.message.isOpenID1()

        if args == {}:
            return None

        self.parseExtensionArgs(args, is_openid1)
        return self