在Django guardian中，我如何确定哪个组给了用户访问对象实例的权限？

from django.contrib.auth.models import User
from guardian.shortcuts import get_groups_with_perms, get_perms_for_model

def get_user_object_permissions(user, object_instance):
    # 获取用户所属的所有组
    groups = user.groups.all()

    # 遍历每个组，获取权限列表
    for group in groups:
        # 获取组对于对象实例的权限列表
        permissions = get_perms_for_model(object_instance, group)

        # 处理权限列表，例如打印权限信息
        for permission in permissions:
            print(f"Group '{group.name}' has permission '{permission}' for object '{object_instance}'")

# 示例用法
user = User.objects.get(username='example_user')
object_instance = MyModel.objects.get(pk=1)
get_user_object_permissions(user, object_instance)