code: def rollback_app(self, app_id, version, force=False):
          
          params = {'force': force}
          data = json.dumps({'version': version})
          response = self._do_request(
              'PUT', '/v2/apps/{app_id}'.format(app_id=app_id), params=params, data=data)
          return response.json()
docs: Roll an app back to a previous version.
  
          :param str app_id: application ID
          :param str version: application version
          :param bool force: apply even if a deployment is in progress
  
          :returns: a dict containing the deployment id and version
          :rtype: dict