'return the authorization url that the user should be redirected to.'

def get_authorize_url(self, redirect_uri='', **kw):

    redirect = (redirect_uri if redirect_uri else self._redirect_uri)
    if (not redirect):
        raise APIError('21305', 'Parameter    absent:    redirect_uri', 'OAuth2    request')
    response_type = kw.pop('response_type', 'code')
    return ('https://graph.qq.com/oauth2.0/authorize?%s' % _encode_params(client_id=self._client_id, response_type=response_type, redirect_uri=redirect, **kw))
