I did this to move my loved resources from deezer to spotify, it succeed but I am working again on this to make a clean and reusable version, so this is a work in progress. The readme is there for anyone that wants to use what is already done!
For now it takes your data from deezer and download them into a JSON file.
Get your SOCIAL_AUTH_DEEZER_KEY and SOCIAL_AUTH_DEEZER_SECRET from Deezer developers website (https://developers.deezer.com/myapps), you will need to create a Deezer App.
Use poetry to install dependencies.
Run a first time the script to get your API_TOKEN, it will open a web browser with the token. The token should get copied to your .env file and then download your deezer loved resources to the backup_deezer.json file.