code: def _get_at_from_session(self):
          
          try:
              return self.request.session['oauth_%s_access_token'
                                          % get_token_prefix(
                                              self.request_token_url)]
          except KeyError:
              raise OAuthError(
                  _('No access token saved for "%s".')
                  % get_token_prefix(self.request_token_url))
docs: Get the saved access token for private resources from the session.