code: def sync_client(self):
          
          if not self._sync_client:
              self._sync_client = AlfSyncClient(
                  token_endpoint=self.config.get('OAUTH_TOKEN_ENDPOINT'),
                  client_id=self.config.get('OAUTH_CLIENT_ID'),
                  client_secret=self.config.get('OAUTH_CLIENT_SECRET')
              )
          return self._sync_client
docs: Synchronous OAuth 2.0 Bearer client