chapter-8.1-modules.md

Chapter 8.1 Python Modules

• Module is a collection of different classes, functions and variables
• A module is nothing but a single file which can be imported into another file.

basic structure of a module

📁 working_dir/
    |-- 📄 module.py
    |     📦 variables
    |     📦 functions
    |     📦 classes
    |
    |-- 📄 main.py
          📦 imports from module.py
          📦 extra logic/code

File 1: school.py

class Student:
    def __init__(self, name, roll):
        self.name = name
        self.roll = roll

File 2: main.py

from school import Student
john = Student('John Doe', 1)
jane = Student('Jane Doe', 1)

Importing the whole module

if animal.py is the filename for the module, the name of the module would be animal. so we can import the whole module by the following command.

import animal

Importing the whole module imports everything that is defined, imported, and initialized inside the module.

Importing individual elements from the module

we can use from keyword to import the individual component from the module. For example the module animal contains the class DomesticAnimal, we can import it using the following command.

from animal import DomesticAnimal
# we can also import multiple elements in the single line using comma
from animal import DomesticAnimal, WildAnimal

# we can also use small brackets so that we can import in different lines

from animal import (
    Animal,
    DomesticAnimal,
    WildAnimal,
)