Reference library

Modern tooling

uv, ruff, pyproject.toml, packaging, and current Python project workflows.

1 match
Modern tooling easy

pytest mark slow skip integration

Uses pytest markers to select fast tests, skip unfinished ones, and run integration checks with verbose output.

pytest markers testing
Python 
import pytest

def test_fast():
    assert 1 + 1 == 2

@pytest.mark.slow
def test_slow():
    import time
    time.sleep(1)
    assert 5 * 5 == 25

@pytest.mark.skip(reason="Not ready for production")
def test_skipped():
    assert 2 + 2 == 5

@pytest.mark.integration
def test_integration():
    database = {"users": […
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Modern tooling — Python code examples

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This page collects modern tooling snippets — short, copy-ready Python you can paste into our free online IDE and run without installing anything. Each sample includes a plain-English explanation and the full source code.

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Related coding tools

Free online Python IDE Write and run Python in your browser — no install. Free Python code formatter Format with autopep8 — side-by-side PEP 8 cleanup. Python code samples Copy-ready snippets to study and run in the IDE.