Explain Python Modules and Packages

 

Python Modules and Packages Explained

In Python, modules and packages are essential concepts for organizing and reusing code.

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1. What is a Module?

A module is a single Python file that contains functions, classes, or variables. It helps to break down large programs into smaller, manageable pieces.

Example:

Create a file called math_utils.py:

# math_utils.py
def add(a, b):
    return a + b

def subtract(a, b):
    return a - b

How to Import a Module:

import math_utils

print(math_utils.add(5, 3))  # Output: 8
print(math_utils.subtract(10, 4))  # Output: 6

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2. What is a Package?

A package is a folder that contains multiple modules. It makes it easier to group related modules together.

A package must contain a special file called __init__.py (even if it's empty). This file tells Python that the folder is a package.

Example Folder Structure:

my_package/
│
├─ __init__.py        # Marks the folder as a package
├─ math_utils.py      # Module 1
└─ string_utils.py    # Module 2

How to Use a Package:

from my_package import math_utils
from my_package import string_utils

print(math_utils.add(5, 3))

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Differences Between Modules and Packages

Feature	Module	Package
Structure	Single file	Folder with multiple modules
Import	import module	from package import module
Use Case	Small code	Large projects
Example	math_utils.py	my_package/

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Bonus 

You can create Sub-Packages by nesting folders.

Example:

my_project/
├─ ecommerce/
│   ├─ __init__.py
│   ├─ cart.py
│   └─ products.py
└─ __init__.py

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 Conclusion

Concept	Purpose	Example
Module	Code reuse	math_utils.py
Package	Code organization	my_package/
Sub-Package	Nested structure	ecommerce/

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