Step-by-step articles on Python, part of our Scripting Languages collection.
Showing 10 articles
Python 3.14 was released in October 2025. Here are the changes most developers will notice. Template strings (t-strings) A t-string looks like an f-string but produces a Template object instead of a finished string. Libraries can then process the interpolated...
uv is a Python package and project manager written in Rust. It replaces pip, pip-tools, virtualenv, pyenv and pipx with one tool, and it's dramatically faster. Install curl -LsSf https://astral.sh/uv/install.sh | sh # or: pipx install uv, brew install uv Start...
Type hints don't change how Python runs, but editors and type checkers use them to catch bugs and power autocomplete. Modern Python syntax makes them short and readable. The basics def greet(name: str, times: int = 1) -> str: return ", ".join([f"Hello {name}"]...
Both give you classes with typed fields and less boilerplate. The key difference: dataclasses store data, Pydantic validates and converts it. Dataclasses from dataclasses import dataclass, field @dataclass(frozen=True, slots=True) class Money: amount: int # pa...
asyncio lets one thread wait on many network operations at once. It shines for I/O-heavy work: calling APIs, scraping, chat servers, database queries. The basics import asyncio import httpx async def fetch_status(client: httpx.AsyncClient, url: str) -> int: re...
match looks like a switch statement, but it's more powerful: it can check the shape of data and pull values out of it in one step. Literals and alternatives def http_message(status: int) -> str: match status: case 200 | 201: return "OK" case 404: return "Not f...
pytest is the standard testing tool for Python. Tests are plain functions using plain assert , and pytest's output shows exactly what differed. First tests # test_pricing.py import pytest from pricing import apply_discount def test_ten_percent_discount(): asse...
Ruff is a Python linter and formatter written in Rust. It implements rules from Flake8 and many of its plugins, sorts imports like isort, and formats code in a Black-compatible style, typically in a fraction of a second. Install and run uv add --dev ruff uv ru...
A list holds every item in memory. A generator produces items one at a time, on demand. For large files, streams or infinite sequences, that's the difference between working and running out of memory. yield def read_lines(path): with open(path) as f: for line...
For decades, CPython's Global Interpreter Lock (GIL) allowed only one thread to run Python bytecode at a time. Threads helped with I/O, but not with CPU-heavy work. Free-threaded builds of Python remove the GIL. The timeline Python 3.13 introduced an experimen...
