[Python] How to get the estimated remaining time of an already started Celery task?

I am using django with Celery and redis. I would like that when a user initiates a Celery task my app estimates the amount of time left until the task is completed(so that I can, for example, represent this data to the frontend as a progress bar).

For example, given this polling function:

views.py:

@csrf_protect
def initiate_task(request):
task = new_celery_task.delay(parmeter_1, parametr_2)

@csrf_protect
def poll_task_status(request, task_id): #task_id provided by frontend

import base64
task_result = AsyncResult(task_id)

if task_result.ready():
try:
...

response_data = {
'status': 'completed',
}

except Task.DoesNotExist:
return JsonResponse({'status': 'error', 'message': 'There has been an error'}, status=404)

elif task_result.state == 'REVOKED':
return JsonResponse({'status': 'terminated', 'message': 'Task was terminated'})

else:
#add code to calculate estimated remaining time here
remaining_time_est = estimate_remaining_time() #estimate task by id
return JsonResponse({'status': 'pending'
#add code to return estimated remaining time here
'est_remaining_time':remaining_time_est
})


and task:

task.py:

app = Celery('myapp')#
@app.task
def new_celery_task(arg_1, arg_2):
#complete task


How would I estimate the remaining time left on an initiated task?

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