'Gets information about a user access token issued by an app. See
<https://developers.facebook.com/docs/facebook-login/
access-tokens/debugging-and-error-handling>
We can generate the app access token by concatenating the app
id and secret: <https://developers.facebook.com/docs/
facebook-login/access-tokens#apptokens>'

def debug_access_token(self, token, app_id, app_secret):

    args = {'input_token': token, 'access_token': '{0}|{1}'.format(app_id, app_secret)}
    return self.request(((self.version + '/') + 'debug_token'), args=args)
