Refactor the code
- `models/` use classes instead of functions 
- split the code more clearly between the app and the worker (in particular: two config files). Possibly, three directories: common or database, worker (or dataset_worker, split_worker), app. It will make it easier to start https://github.com/huggingface/datasets-server/
Refactor the code: - `models/` use classes instead of functions 
- split the code more clearly between the app and the worker (in particular: two config files). Possibly, three directories: common or database, worker (or dataset_worker, split_worker), app. It will make it easier to start https://github.com/huggingface/datasets-server/