The Label Studio ML Backend (https://github.com/HumanSignal/label-studio-ml-backend/) is an SDK that lets you wrap your machine learning code and turn it into a web server. The web server can be connected to a running Label Studio instance to automate labeling tasks. 

You can find ML backend examples for Label Studio studio here:
https://github.com/HumanSignal/label-studio-ml-backend/tree/master/label_studio_ml/examples

This folder (label-studio/label_studio/ml) is an API that interacts with Label Studio ML Backends.