What to put in __init__.py after I add a class inside a class when making a Python module? [closed]

So I have a module I am making called matlypy

I wanted to make another class inside another class but that returned a error.

I want to keep the class in class but what do I have to put in __init__.py?

""" # MatlPY it is recommended to read the README.md for full documentation, the following text is a mere summary! MatlyPY is a combination of Matplotlib.pyplot and Numpy with included ML presets. You can also do matrix & tensor calculations. Although the lib is very fast its still a good lib. """ from .plotting import plot from .mathematics import math from .model import model