In Directory

Any folder that contains __init___ becomes a Python package.

__init___ serves to:

• Initialize package-level variables.
• point where external locations can import submodules or contents from.
• Avoids circular imports.

Meaning, you should place __init__.py in a directory to make it a package, allowing you to import modules from that directory.

# myapp/routes/__init__.py
from .routes import users
from .routes import products
from .routes import orders

# external
from myapp.routes import users

In Class

__init__ is a constructor in a python class:

class MyClass:
    def __init__(self, name):
        self.name = name