🐍 Python – Zero to Advanced

🌐 Learning Goal

Master Python completely — from first program to advanced patterns — with every concept compared side-by-side to JavaScript so you learn twice as fast.

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🎯 Who Is This For?

Developers who already know JavaScript / Node.js and want to learn Python quickly by mapping what they already know.

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🛠️ Prerequisites

• Basic understanding of JavaScript (variables, functions, loops, classes)
• Node.js installed (for JS comparisons)
• Python 3.10+ installed

# Verify both are installed
node --version     # JS runtime
python3 --version  # Python runtime

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📁 Lesson Files

python-lessons/
├── README.md                    ← You are here (master index)
│
├── 01_setup.md                  ← Installation, REPL, first program
├── 02_variables.md              ← Variables, types, type conversion
├── 03_strings.md                ← Strings, f-strings, all methods
├── 04_numbers.md                ← Numbers, math operators, math module
├── 05_control_flow.md           ← if/elif/else, loops, break/continue
├── 06_lists.md                  ← Lists, slicing, comprehensions
├── 07_tuples.md                 ← Tuples, packing, unpacking
├── 08_dictionaries.md           ← Dicts, methods, dict comprehensions
├── 09_sets.md                   ← Sets, operations, use cases
├── 10_functions.md              ← def, args, kwargs, lambda, scope
├── 11_decorators.md             ← @decorator, closures, functools
├── 12_generators.md             ← yield, generator expressions, lazy eval
├── 13_oop_basics.md             ← Classes, __init__, self, methods
├── 14_oop_advanced.md           ← Inheritance, magic methods, dataclass
├── 15_modules.md                ← import, packages, __name__
├── 16_pip_venv.md               ← pip, virtual environments, requirements
├── 17_file_handling.md          ← open(), read, write, with statement
├── 18_error_handling.md         ← try/except/finally, custom exceptions
├── 19_json_csv.md               ← json module, csv module
├── 20_stdlib.md                 ← os, sys, pathlib, datetime, random, re
├── 21_type_hints.md             ← Type annotations, typing module, mypy
├── 22_async.md                  ← async/await, asyncio, httpx
├── 23_regex.md                  ← re module, patterns, match/search/sub
├── 24_collections.md            ← Counter, defaultdict, deque, namedtuple
├── 25_testing.md                ← pytest, assertions, fixtures, mocking
└── 26_best_practices.md         ← PEP 8, clean code, tools

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📊 Curriculum Phases

Phase 1 — Fundamentals (Lessons 01–04)

Get Python running and understand the basic building blocks.

Phase 2 — Control Flow (Lesson 05)

Make decisions and repeat operations.

Phase 3 — Data Structures (Lessons 06–09)

Python's powerful built-in collections.

Phase 4 — Functions (Lessons 10–12)

Write reusable, expressive, Pythonic functions.

Phase 5 — OOP (Lessons 13–14)

Design programs with classes and objects.

Phase 6 — Modules & Ecosystem (Lessons 15–16)

Organise code and use Python's massive library ecosystem.

Phase 7 — File & Error Handling (Lessons 17–19)

Read files, process data, handle failures.

Phase 8 — Advanced Python (Lessons 20–24)

Standard library, type hints, async, regex, collections.

Phase 9 — Testing & Best Practices (Lessons 25–26)

Write code that works, lasts, and others can read.

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🔐 JS vs Python — Quick Mental Map

JavaScript	Python	Notes
let / const	just =	No declaration keyword
console.log()	print()	Output
null	None	No value
true / false	True / False	Capital letters!
===	==	Python has no ===
{} blocks	indentation	4 spaces = block
Array	list	Most methods differ
Object	dict	Keys must be quoted
function / =>	def / lambda
class + constructor	class + __init__
this	self	Must be explicit
try/catch	try/except
...spread	*args / **kwargs
async/await	async/await + asyncio
Template literals	f-strings	f"Hello {name}"

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🚀 Setup Instructions

1️⃣ Install Python

# Download from https://python.org
python3 --version   # verify

2️⃣ Install a Code Editor

VS Code + Python extension (IntelliSense, linting, debugging)

3️⃣ Create Virtual Environment

python3 -m venv venv
source venv/bin/activate    # Mac/Linux
venv\Scripts\activate       # Windows

4️⃣ Run Your First File

echo 'print("Hello, World!")' > hello.py
python3 hello.py

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✅ Lesson Conventions

Each lesson file follows this structure:

🎯 What you'll learn
📌 JS vs Python comparison (side by side)
💡 Key concepts explained
🧪 Code examples with output
⚠️  Common mistakes / gotchas
🔗 What to learn next

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