Your app's a mess, but the Django maid can help! Django maid gets rid of files that have been orphaned—either because their models have been deleted or because they've been replaced with newer versions. No more messy media directories while the django maid's on the job!

1. pip install -e git+https://github.com/matthewwithanm/django-maid.git#egg=django-maid
2. Add maid to INSTALLED_APPS in settings.py.

from myapp.models import MyModel
import maid

maid.register_file_fields(MyModel, ['document', 'thumbnail_image'])

Maid will now automatically delete files stored in the document and thumbnail_image properties of MyModel when they're orphaned.

If you have a non-standard setup where files are shared between different models, you should manage the deletion of files yourself. Django-maid can't tell that the file is being used somewhere else, so she might throw out something that you didn't want her to.