# from openid.extensions.ax import fromSuccessResponse

    def fromSuccessResponse(cls, success_response, signed=True):
        """Construct a FetchResponse object from an OpenID library
        SuccessResponse object.

        @param success_response: A successful id_res response object
        @type success_response: openid.consumer.consumer.SuccessResponse

        @param signed: Whether non-signed args should be
            processsed. If True (the default), only signed arguments
            will be processsed.
        @type signed: bool

        @returns: A FetchResponse containing the data from the OpenID
            message, or None if the SuccessResponse did not contain AX
            extension data.

        @raises AXError: when the AX data cannot be parsed.
        """
        self = cls()
        ax_args = success_response.extensionResponse(self.ns_uri, signed)
        try:
            self.parseExtensionArgs(ax_args)
        except NotAXMessage, err:
            return None
        else:
            return self

    fromSuccessResponse = classmethod(fromSuccessResponse)