Python module import

__init__.py

#This is ecommerce/__init__.py file
#If there is a __init__.py in a folder, it makes it a package :)

app.py

#Import single function
#from ecommerce.shipping import calc_shipping
#calc_shipping()

#Import single module
#import ecommerce.shipping
#ecommerce.shipping.calc_shipping()

#Import single module, skip package name
from ecommerce import shipping
shipping.calc_shipping()

shipping.py

#ecommerce/shipping.py
#Function inside shipping module
def calc_shipping():
    print("calc_shipping")