nicht unterstütztes Medienart Django

You are probably sending your request with a MIME type that your method is not ready to work with.

Check out the media types in here:
https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types/Complete_list_of_MIME_types

Can't say much without looking at your request, but i hope it helps.
Santino