Run Celery Tasks at the end of all others celery tasks

Question

I have First Function say A. This function will call Celery Task Cel_task1 in a loop and for each Cel_task1 will call another celery task Cel_task2 and each Cel_task2 will call celery task Cel_task3 and Cel_task3 will calculate result and save to DB.

def A==> **Cel_task1* -->**Cel_task2**-->**Cel_task3**

I want to run a celery task at the end of all other celery tasks. and will use the result of the Cel_task3