old_contents: from django.contrib import admin
  
  # Register your models here.
  from .models import Category, Product, Transaction, UserTag, ProductTag
  
  admin.site.register(Product)
  admin.site.register(Category)
  admin.site.register(Transaction)
  admin.site.register(UserTag)
  admin.site.register(ProductTag)
  
new_contents: from django.contrib import admin
  from django.contrib.auth.admin import UserAdmin
  from django.contrib.auth.models import User
  
  from .models import Category, Product, Transaction, UserTag, ProductTag, Account
  
  
  class AccountInline(admin.StackedInline):
      model = Account
      can_delete = False
      verbose_name_plural = 'Account'
      fk_name = 'user'
  
  class CustomUserAdmin(UserAdmin):
      inlines = (AccountInline, )
      list_display = ('email', 'is_staff', 'is_superuser', 'last_login', 'balance')
      list_select_related = ('account', )
  
      def get_inline_instances(self, request, obj=None):
          if not obj:
              return list()
          return super(CustomUserAdmin, self).get_inline_instances(request, obj)
  
      def balance(self, instance):
          return instance.account.balance
  
  admin.site.unregister(User)
  admin.site.register(User, CustomUserAdmin)
  
  admin.site.register(Product)
  admin.site.register(Category)
  admin.site.register(Transaction)
  admin.site.register(UserTag)
  admin.site.register(ProductTag)
  
subject: Modify user information in admin panel to be sensible