How to wait for Celery task result in asynchronous RestAPI?

I have an API build with FastAPI which endpoint submits a task to a celery worker, waits for worker to finish its job and return a result to the user.

Question is what is the correct way to wait the result?

Endpoint code

from tasks import celery_application, some_task
from celery.result import AsyncResult

@api.post('/submit')
async def submit(data: str):
    task = some_task.apply_async(kwargs={'data': data}, queue='some_queue')
    result = AsyncResult(id=task.task_id, app=celery_application).get()
    return {'task_result': result}

The problem with AsyncResult that it is that get method blocks the application, it waits for the result synchronously and the api freezes in the meantime.

One of the solutions I came up with is checking for result in a loop for n seconds

from tasks import celery_application, some_task
import asyncio
import redis


r = redis.Redis.from_url(REDIS_CONN_URI)


@api.post('/submit')
async def submit(data: str):
    task = some_task.apply_async(kwargs={'data': data}, queue='some_queue')
    result = None
    for _ in range(100):
        if r.exists(task.task_id):
            result = r.get(task.task_id)
            break
        await asyncio.sleep(0.3)

    return {'task_result': result}

But it only works partially. Although endpoint is not blocked and can be accessed. Endpoint gets blocked when it tries to reach send task again.