django runscript error: no (valid) module for script 'main' found

Running Extra scripts in Django:

1. Create scripts directory in your root project, next to manage.py:

   $ mkdir scripts
   

2. Add an empty file init.py (double underscore) into your /scripts directory:

   $ touch scripts/__init__.py
   

   The init file is necessary so that the folder is picked up as a python package.

   This is probably what you're missing.

3. Add your scripts into /scripts directory:

   $ touch scripts/main.py
   

4. After you edited your main.py script, run it with:

   $ python manage.py runscript script-name
   

   Note: You shouldn’t include .py when specifying the script to run

Checkout Runscript Documentation