Overriding AppConfig.ready()

Trying to catch the basics of Django. Namely how Applications work. The docs: https://docs.djangoproject.com/en/stable/ref/applications/#methods

And in the code of the class AppConfig we can read:

def ready(self):
    """
    Override this method in subclasses to run code when Django starts.
    """

Well, this is my example:

my_app/apps.py

class MyAppConfig(AppConfig):
    name = 'my_app'

    def ready(self):
        print('My app')

I just want to make the ready method work. That is, when Django finds my_app, let it run the ready method.

The app is registered in INSTALLED_APPS.

I execute 'python manage.py runserver'. And nothing is printed.

If I place a breakpoint inside the ready method, the debugger don't stop there.

Could you help me: what is my mistake in understanding here. Thank you in advance.

INSTALLED_APPS = [
    'django.contrib.admin',
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'my_app',
]

And I created a view

my_app/views.py

def index(request):
    print('Print index')

urls.py

urlpatterns = [
    url(r'^admin/', admin.site.urls),
    url(r'^$', my_app_views.index, name='home')
]

Well, the view is working. This means that the application is registered.