未能加载资源:服务器响应状态为504(网关超时)

I am developing a project using django - python, javascript. When I call a long running process (time-consuming) approx more than 20 minutes from views the process starts successfully. I used loader in ajax to notify user that process is running. After the process completes the loader will stop and change to completed state. I am developing a project using django - python