When you call functions using delay, it will return Task object. Using that task object you can see the status and after successful you can retrieve result using task object.
ERROR: for app Cannot start service app: driver failed programming external connectivity on endpoint backend_drf_app_1 (19dab13b974c1e428b2c668845755a51c216df1456adab268e41c32d34866de6): Bind for 0.0.0.0:8000 failed: port is already allocated
ERROR: Encountered errors while bringing up the project.
docker-compose down
docker rm -fv $(docker ps -aq)
lsof -i -P -n | grep 5432
출처: https://nayha.tistory.com/625 [Nayha]
WARNING: Found orphan containers (backend_drf_worker_1) for this project. If you removed or renamed this service in your compose file, you can run this command with the --remove-orphans flag to clean it up.