Modulas and packages in python

 

Here is a clear and easy explanation of Modules in Python, perfect for beginners:

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📌 Modules in Python

A module in Python is simply a file that contains Python code — functions, variables, classes, etc.
It helps you:

✔️ Organize code
✔️ Reuse code
✔️ Keep programs clean and manageable

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🧩 Types of Modules

1. Built-in Modules

These come pre-installed with Python.
Example: math, random, os, datetime

import math

print(math.sqrt(25))  # Output: 5.0

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2. User-Defined Modules

Modules created by you.

Example:
Create a file my_module.py

def add(a, b):
    return a + b

pi = 3.14

Now import it in another file:

import my_module
print(my_module.add(5, 3))  # Output: 8

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3. Third-Party Modules

Installed using pip.

Example:

pip install numpy

Then use it:

import numpy as np
print(np.array([1, 2, 3]))

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📥 Importing a Module

1. import module_name

import math
print(math.factorial(5))

2. from module import function

from math import sqrt
print(sqrt(16))

3. from module import * (not recommended)

from math import *
print(sin(1))

4. import module as alias

import math as m
print(m.pi)

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📚 Why Use Modules?

✔ Avoid repeating code
✔ Easier debugging
✔ Better organization
✔ Use powerful libraries like NumPy, Pandas, Matplotlib

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🔍 Checking Available Modules

help('modules')

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📦 Creating and Using Your Own Module

Step 1: Create a file named calculator.py

def add(a, b):
    return a + b

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

Step 2: Import it

import calculator

print(calculator.add(10, 20))

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If you want, I can also give:

📘 Notes (PDF style)

📚 Examples with output
🧩 Practice questions

Just tell me!

Here is a very clear and simple explanation of Modules and Packages in Python—perfect for beginners.

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✅ Modules and Packages in Python

📌 1. What is a Module?

A module is a single Python file (.py) that contains functions, variables, classes, or code.

✔ Example: Creating a module

Create a file named calculator.py:

def add(a, b):
    return a + b

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

Use the module in another file:

import calculator

print(calculator.add(5, 3))  # Output: 8

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📦 2. What is a Package?

A package is a collection of modules inside a folder.
The folder must contain a special file named:

__init__.py

This file makes Python treat the folder as a package.

📁 Example package structure:

my_package/
    __init__.py
    calculator.py
    greetings.py

✔ Using a module inside a package:

from my_package import calculator
print(calculator.add(10, 5))

Or:

from my_package.calculator import add
print(add(10, 5))

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🔍 Difference Between Module and Package

Feature	Module	Package
Definition	Single Python file	Folder containing modules
File	module.py	Folder with __init__.py + modules
Purpose	Organize code	Organize multiple modules
Example	math.py	numpy package

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🧩 Real-Life Examples

Built-in Modules

• math, random, os, time

Built-in Packages

• email, xml, asyncio

Third-party Packages (installed via pip)

• numpy
• pandas
• matplotlib

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🔧 How to Create Your Own Package

Step 1: Create a folder

my_tools/

Step 2: Add __init__.py (can be empty)

my_tools/
    __init__.py

Step 3: Add modules

my_tools/
    __init__.py
    math_ops.py
    string_ops.py

Step 4: Use it

from my_tools.math_ops import add
print(add(4, 2))

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⭐ Summary

• Module = A single Python file.
• Package = A folder containing multiple modules.
• Packages help organize large programs.

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If you'd like, I can also provide:

📘 Notes (PDF style)
🐍 Python programs for module & package
📝 Practice questions
📦 Real project example with packages

Just tell me!