Registering models in admin in Django - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ component_behavior

intermediate

What is the output when accessing the Django admin after registering a model incorrectly?

Consider the following Django admin registration code:

from django.contrib import admin
from .models import Book

admin.site.register(Book())

What happens when you try to access the Django admin page for the Book model?

Django

from django.contrib import admin
from .models import Book

admin.site.register(Book())

A Raises a TypeError because an instance is passed instead of the model class.

B The admin page shows the Book model list correctly.

C The admin page shows but with no data listed.

D Raises an ImportError due to wrong import syntax.

💡 Hint

Remember that admin.site.register() expects a model class, not an instance.

The admin.site.register() function requires the model class itself, not an instance. Passing Book() creates an instance, which causes a TypeError.

📝 Syntax

intermediate

Which code correctly registers multiple models in Django admin?

You want to register two models, Author and Publisher, in the Django admin. Which of the following code snippets is correct?

A admin.site.register(Author, Publisher)

B admin.site.register({Author, Publisher})

C admin.site.register(Author); admin.site.register(Publisher)

D admin.site.register([Author, Publisher])

💡 Hint

Think about how to register multiple models separately or together.

Each model must be registered individually or passed as a list. Option C registers each model separately, which is correct. Option C is close but Django expects a list, not a tuple or set. Option C passes two arguments incorrectly. Option C uses a set which is invalid.

🔧 Debug

advanced

Why does this custom admin class not apply to the model in Django admin?

Given this code:

from django.contrib import admin
from .models import Article

class ArticleAdmin(admin.ModelAdmin):
    list_display = ('title', 'published_date')

admin.site.register(Article)

Why does the admin page not show the custom list display?

Django

from django.contrib import admin
from .models import Article

class ArticleAdmin(admin.ModelAdmin):
    list_display = ('title', 'published_date')

admin.site.register(Article)

A Because admin.site.register requires a decorator.

B Because list_display is not a valid attribute for ModelAdmin.

C Because the Article model is not imported correctly.

D Because the admin class ArticleAdmin was not passed to admin.site.register.

💡 Hint

Check how the admin class is linked to the model registration.

The custom admin class must be passed as the second argument to admin.site.register() to apply its settings. Without it, the default admin is used.

❓ state_output

advanced

What is the effect of this admin registration with a decorator?

Consider this Django admin code:

from django.contrib import admin
from .models import Event

@admin.register(Event)
class EventAdmin(admin.ModelAdmin):
    list_display = ('name', 'date')

What happens when you access the admin page for Event?

Django

from django.contrib import admin
from .models import Event

@admin.register(Event)
class EventAdmin(admin.ModelAdmin):
    list_display = ('name', 'date')

A The Event model is registered with the custom EventAdmin showing name and date columns.

B The Event model is registered but uses default admin settings ignoring list_display.

C Raises a SyntaxError because decorators cannot be used with admin classes.

D The Event model is not registered at all.

💡 Hint

Think about what the @admin.register() decorator does.

The decorator registers the model with the specified admin class, applying its configuration such as list_display.

🧠 Conceptual

expert

What error occurs if you register the same model twice with different admin classes?

Given this code snippet:

from django.contrib import admin
from .models import Product

class ProductAdmin1(admin.ModelAdmin):
    list_display = ('name',)

class ProductAdmin2(admin.ModelAdmin):
    list_display = ('price',)

admin.site.register(Product, ProductAdmin1)
admin.site.register(Product, ProductAdmin2)

What happens when Django starts?

Django

from django.contrib import admin
from .models import Product

class ProductAdmin1(admin.ModelAdmin):
    list_display = ('name',)

class ProductAdmin2(admin.ModelAdmin):
    list_display = ('price',)

admin.site.register(Product, ProductAdmin1)
admin.site.register(Product, ProductAdmin2)

A Raises a SyntaxError due to duplicate registration.

B Raises django.contrib.admin.sites.AlreadyRegistered error.

C Both admin classes are merged and applied.

D The second registration overrides the first without error.

💡 Hint

Think about how Django admin handles multiple registrations of the same model.

Django admin raises an AlreadyRegistered exception if you try to register the same model more than once without unregistering it first.