Django中的Sync_to_Async修饰器、异步视图

我正在努力学习视频教程，并try 理解Django中的异步视图和@sync_to_async修饰器.

我有这样的代码:

import time
import asyncio

from asgiref.sync import sync_to_async
from django.http import HttpResponse

from movies.models import Movie
from stories.models import Story



@sync_to_async
def get_movies_async():
    print('prepare to get the movies...')
    time.sleep(2)
    qs = Movie.objects.all()
    print('got all the movies')


@sync_to_async
def get_stories_async():
    print('prepare to get the stories...')
    time.sleep(5)
    qs = Story.objects.all()
    print('got all the stories')



async def main_view_async(request):
    start_time = time.time()
    await asyncio.gather(get_movies_async(), get_stories_async())
    total = (time.time() - start_time)
    print("total: ", total)
    return HttpResponse('async!')

But when I call main_view_async from my browser it still takes 7 seconds, not 5 seconds like in the video tutorial.
The tutorial might be outdated (year 2020). Or perhaps I am doing something wrong? Can you please help?

My output

prepare to get the movies...
got all the movies
prepare to get the stories...
got all the stories
total:  7.0126471519470215

The tutorial terminal output个

prepare to get the movies...
prepare to get the stories...
got all the movies
got all the stories
total:  5.0126471519470215