How to make easily an administration interface for the whole project

On versions of Django < 2.1, it was impossible to overload the administration “properly”.

• Create a file admin.py at the root of your project (“at the root”, because it is “global” for the whole project)
• Put that code:
  from django.contrib import admin
class MyProjectAdminSite(admin.AdminSite):
    title_header = 'My project Admin'
    site_header = 'My project administration'

  Of course, change “MyProject” to the name of your project…
• In settings.py, replace 'django.contrib.admin' by 'my_app.apps.MyAppAdminConfig',
• In the file apps.py of your project, hence my_project/my_app/apps.py, declare the administration like this:
  from django.apps import AppConfig
from django.contrib.admin.apps import AdminConfig
class MyAppConfig(AppConfig):
    name = 'my_app'
class MyAppAdminConfig(AdminConfig):
    default_site = 'admin.MyProjectAdminSite'

And… that’s it!