I have a directory that stores all the .py files.
bin/ main.py user.py # where class User resides dir.py # where class Dir resides
Just too brief, Create a file __init__.py is classes directory and then import it to your script like following (Import all case)
__init__.py
from classes.myscript import *
Import selected classes only
from classes.myscript import User from classes.myscript import Dir