Customize model manager in django

I am working on a django blog project.

this is my models.py code:

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

# Create your models here.

class PublishManager(models.Manager):
    def get_queryset(self):
        return super().get_queryset().filter(status=Post.Status.PUBLISHED)


class Post(models.Model):
    class Status(models.TextChoices):
        DRAFT = 'DF', 'Draft'
        PUBLISHED = 'PB', 'Published'

    user = models.ForeignKey(User,on_delete=models.CASCADE,related_name="blog_posts")
    title = models.CharField(max_length=250)
    slug = models.SlugField(max_length=250)
    body = models.TextField()
    publish = models.DateTimeField(default=timezone.now)
    created = models.DateTimeField(auto_now_add=True)
    updated = models.DateTimeField(auto_now=True)
    status = models.CharField(max_length=2,choices=Status.choices,default=Status.DRAFT)
    objects = models.Manager()
    published = PublishManager()
    class Meta:
        ordering = ['-publish']
        indexes = [
            models.Index(fields=['-publish'])
        ]


    def __str__(self):
        return self.title

when i put “published = PublishManager()“ on top of “objects = models.Manager()” like this:

    published = PublishManager()
    objects = models.Manager()

i found that my admin site didnt show the entry with draft status.

if i create a Post object with status equal Published,then it will be show in my admin site.if i create an object with status Draft,it won't show in admin site.

i don't know why,could anyone can help me?

i guess, maybe the default manager is the first manager.the admin site use the first manager to show all entry.