'Extends the expiration time of a valid OAuth access token. See
<https://developers.facebook.com/roadmap/offline-access-removal/
#extend_token>'

def extend_access_token(self, app_id, app_secret):

    args = {'client_id': app_id, 'client_secret': app_secret, 'grant_type': 'fb_exchange_token', 'fb_exchange_token': self.access_token}
    return self.request('access_token', args=args)
