Reference library

Python Code Samples

Easy snippets you can copy, study, and run in the browser editor.

1 match
Testing & modern typing easy

How to mark known bugs with pytest xfail in Python

Use @pytest.mark.xfail to mark tests that are expected to fail due to known bugs, with optional strict mode to control pass/fail behavior.

pytest testing xfail
Python
import pytest


def divide(a: int, b: int) -> float:
    if b == 0:
        raise ZeroDivisionError("Cannot divide by zero")
    return a / b


@pytest.mark.xfail(reason="Known bug: division returns int instead of float", strict=False)
def test_divide_integer_division():
    result = divide(10, 4)
    assert isinstanc…
16 0 Open

Browse by section

Each section groups closely related Python snippets.

Guide: free Python code samples library

Copy-ready Python snippets for learners and developers

PythonSkillset code samples are short, focused examples organised by topic and difficulty. Every snippet is server-rendered HTML — readable by search engines and easy to copy. Open any sample, read the notes, copy the code, then press Try in editor to run it in the browser with Pyodide.

How to use this library

  1. Pick a topic section — strings, lists, files, functions, and more
  2. Open a sample, read How it works, and copy the code block
  3. Run it in the IDE, tweak values, then take a related quiz or tutorial lesson

Samples vs tutorials and challenges

Samples are quick reference — one concept per page. For step-by-step teaching, use our Python tutorials. To test yourself, try quizzes or coding challenges. Clean up style with the Python formatter.