Hello folks 
Our new article might be interesting / of use to you - Direct to S3 file upload with Django
It builds on top of the idea for “direct uploads” - where you bypass the backend, by uploading straight to S3, for example.
In addition to that, it makes use of django-storages, so we can have a File model that supports both direct uploads & standard uploads (for example - via the Django admin)
There are plenty of code examples - they can be used directly, or cherry-picked & altered for your specific case.
Feedback is always appreciated 
Cheers 