old_contents: from django.contrib import admin
  
  from .models import User
  
  
  admin.site.register(User)
  
new_contents: from django.contrib import admin
  
  from .models import User
  
  
  class UserAdmin(admin.ModelAdmin):
      list_display = ('id', 'username')
  
  admin.site.register(User, UserAdmin)
  
subject: add userAdmin