'Form an authorization URL.
:param url: Authorization endpoint url, must be HTTPS.
:param state: An optional state string for CSRF protection. If not
given it will be generated for you.
:param kwargs: Extra parameters to include.
:return: authorization_url, state'

def authorization_url(self, url, state=None, **kwargs):

    state = (state or self.new_state())
    return (self._client.prepare_request_uri(url, redirect_uri=self.redirect_uri, scope=self.scope, state=state, **kwargs), state)
