如何检查多对多字段中是否存在Django用户？

from django.db import models
from django.contrib.auth.models import User

class Post(models.Model):
    title = models.CharField(max_length=200)
    content = models.TextField()
    likes = models.ManyToManyField(User, related_name='liked_posts')

# 检查用户是否点赞了某个帖子
def is_user_liked_post(user, post):
    return post.likes.filter(id=user.id).exists()

# 使用示例
user = User.objects.get(username='example_user')
post = Post.objects.get(id=1)
if is_user_liked_post(user, post):
    print("用户已经点赞了这个帖子")
else:
    print("用户还没有点赞这个帖子")

# 使用prefetch_related优化查询
posts = Post.objects.prefetch_related('likes')
for post in posts:
    if is_user_liked_post(user, post):
        # 处理逻辑