🐍 Python for TypeScript Developers

A structured exercise repo designed specifically for full-stack TypeScript/JavaScript developers learning Python. Every exercise shows the TypeScript equivalent side-by-side so you can leverage what you already know.

Who this is for

You already know TypeScript, Node.js, React/Astro/SolidJS, and backend frameworks like Express, Hono, or Elysia. You want to learn Python without starting from zero — mapping concepts you already understand to Python equivalents.

Structure

📁 01_beginner/          # Python syntax basics (1–2 hrs each)
📁 02_intermediate/      # Pythonic patterns & OOP (2–4 hrs each)
📁 03_advanced/          # Decorators, generators, async (3–5 hrs each)
📁 04_expert/            # Metaclasses, concurrency, build a FastAPI server

Each exercise folder contains:

• README.md — instructions + the TypeScript equivalent for context
• exercise.py — the file you edit (has TODO comments)
• solution.py — reference solution (try not to peek!)
• test_exercise.py — pytest tests to verify your work

Setup

# Python 3.11+ recommended
python --version

# Install pytest for running tests
pip install pytest

# Run all tests for a specific exercise
cd 01_beginner/01_variables_and_types
pytest test_exercise.py -v

# Run all tests in the repo
pytest --tb=short

Progression

Level	Folder	Concepts	Est. Time
🟢 Beginner	01_beginner/	Types, strings, lists, dicts, control flow, functions	8–10 hrs
🟡 Intermediate	02_intermediate/	Comprehensions, classes, modules, file I/O, exceptions	10–15 hrs
🔴 Advanced	03_advanced/	Decorators, generators, async/await, protocols	15–20 hrs
⚫ Expert	04_expert/	Metaclasses, descriptors, concurrency, FastAPI project	20+ hrs

TypeScript → Python Mental Model

When you think...	In Python it's...
const / let	Just assign: x = 5
interface	Protocol (structural) or TypedDict
type MyType = ...	TypeAlias or just a variable
Array<T>	list[T]
Promise<T>	Coroutine[T] + asyncio
async/await	Same! But needs asyncio.run()
try/catch	try/except
throw new Error()	raise ValueError()
...spread	*args / **kwargs
JSON.parse()	json.loads()
Express route app.get(...)	FastAPI @app.get(...)