The best way to understand a software package, is to reverse-engineer it to its simplest form. The following articles do just that. Click to expand.
Peewee vs Django ORM, if you are already using Django:
Quickly translate Django model defintions into Peewee, if wanting to use Peewee:
However, for the sake of being minimalistic in the number of software layers, you can use .raw() in Django to write straight SQL, avoiding ORM altogether.