Setting error message

Let me explain.

  1. I made a folder Mainf in sc folder
    sc folder is Startapp
    2- So in Installed_app Settins I configure
    3- in Mainf I got my Models to migrate

when I run python makemigrations send me this message.

django.core.exceptions.ImproperlyConfigured: Cannot import ‘Mainf’. Check that ‘’ is correct.

Any help please