Running an asynchronous mode Python function with Celery

Question

I have the function test() that takes a long time and I want to execute it asynchronously. I put the decorator of the Celery in the same as below:

from celery import task

@task
def test():
    (...)
    return 'done1

And I execute her doing:

test.delay()

When I run my program it is not put in the background as expected, it performs normally synchronously. I’m forgetting something related to Celery?