I'm just starting to get to the point in my python projects that I need to start using multiple packages and I'm a little confused on exactly how everything is supposed to work together. What exactly should go into the __init__.py of the package? Some projects I see just have blank inits and all of their code are in modules in that package. Other projects implement what seems to be the majority of the package's classes and functions inside the init.
Is there a document or style guide or something that describes what the python authors had in mind for the use of packages and the __init__ file and such?
Edit:
I know the point of having the __init__.py file in the simplest sense that it makes a folder a package. But why would I put a function there instead of a module in that same folder(package)?