def authorize(self, callback_uri, code=<NUM_LIT>):
raise NotImplementedError<EOL>
Redirects to third-part URL and authorizes.

        :param callback_uri: the callback URI. if you generate it with the
                             :func:`~flask.url_for`, don't forget to use the
                             ``_external=True`` keyword argument.
        :param code: default is 302. the HTTP code for redirection.
        :returns: the redirection response.