• Messages framework

Add this to the config:

INSTALLED_APPS = [
    ...
    'django.contrib.sessions',
    ....
 
MIDDLEWARE = [
    ...
    'django.contrib.sessions.middleware.SessionMiddleware',
    ....

To use them:

# Get a session value by its key (e.g. 'my_car'), raising a KeyError if the key is not present
my_car = request.session['my_car']
# Get a session value, setting a default if it is not present ('mini')
my_car = request.session.get('my_car', 'mini')
# Set a session value
request.session['my_car'] = 'mini'
# Delete a session value 
del request.session['my_car']

• https://docs.djangoproject.com/en/2.1/howto/initial-data/