Modern tooling
uv, ruff, pyproject.toml, packaging, and current Python project workflows.
Build a Textual TUI App Skeleton in Python
Create a minimal Textual terminal UI app with a header, label, button, and footer, ready for interactive mock demonstrations.
from textual.app import App, ComposeResult
from textual.widgets import Header, Footer, Button, Label
class MockApp(App):
"""A minimal Textual TUI app skeleton."""
BINDINGS = [("q", "quit", "Quit")]
def compose(self) -> ComposeResult:
"""Create child widgets."""
yield Header()
yie…How to Create Interactive CLI Prompts in Python with questionary
Build mock interactive command-line prompts using questionary's select and text widgets with graceful handling of user cancellation.
import questionary
def main():
# Mock interactive prompts using questionary's select and text
choice = questionary.select(
"What is your favorite programming language?",
choices=["Python", "JavaScript", "Go", "Rust"]
).ask()
# ask() returns None if user cancels; handle gracefully
…How to Load and Inspect Data Files in Python
A beginner-friendly DataLoader dataclass that loads JSON or text files and provides methods to preview and inspect the data.
from dataclasses import dataclass, field
from pathlib import Path
import json
from typing import Any, Dict, List
@dataclass
class DataLoader:
"""Simple helper to load and inspect data files for beginners."""
path: Path
data: Any = field(init=False, default=None)
def __post_init__(self) -> None:
…How to Mock Poetry pyproject.toml Dependencies Sections in Python
Parse and extract dependency lists from Poetry-style pyproject.toml text using Python's standard library.
from pathlib import Path
import re
def parse_pyproject_dependencies(text):
"""Extract dependencies from a pyproject.toml style text."""
lines = text.splitlines()
sections = {
"dependencies": [],
"dev": [],
"optional": [],
}
current_section = None
patterns = {
…Lint a Dockerfile with a Mock Hadolint in Python
A lightweight Python script that simulates hadolint by scanning Dockerfile text for common lint rules and printing violations.
import subprocess
import tempfile
from pathlib import Path
def lint_dockerfile(content: str) -> list[str]:
"""Mock hadolint by checking a few rules and returning violations."""
violations = []
lines = content.splitlines()
for idx, line in enumerate(lines, start=1):
stripped = line.strip()
…Browse by section
Each section groups closely related Python snippets.
Modern tooling — Python code examples
What you will find here
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.
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.