How to add models to the admin panel?

Question

Django

Hello! Added display of my model in the admin panel:


But on the edit page, a void is displayed with the inscription:


Please tell me where I could make a mistake and how to fix it.

admin.py code:

from django.contrib import admin
from shop.models import Product

admin.site.register(Product)

models.py code:

from django.db import models

class Product(models.Model):
    visible = models.BooleanField(default=True)
    sdescr = models.CharField(max_length=40)
    ldescr = models.CharField(max_length=200, null=True)
    cost = models.IntegerField()
    class Meta:
        verbose_name_plural = 'Продукты'
        verbose_name = 'Продукты'

Answer 1

It is necessary to register the relationship of the model with the successor of ModelAdmin, and not the model.