Reference library

Python Code Samples

Copy-ready Python snippets by topic and difficulty — short, focused, and runnable in the browser editor.

8 matches
Files & data easy

How to Validate JSON Schema Shape in Python

Validate JSON data against a schema using manual checks for required fields, types, and constraints.

json validation schema
Python
import json
from typing import Any, Dict

def validate_person_schema(data: Dict[str, Any]) -> bool:
    """Validate a person object against expected schema shape."""
    if not isinstance(data, dict):
        return False
    
    # Required fields check
    required_fields = {"name", "age", "email"}
    if not requir…
12 0 Open
AI & LLM integration patterns easy

How to Validate LLM Output in Python

A beginner-friendly DataValidator class that checks required fields and type constraints on LLM-generated or user JSON data.

validation llm json
Python
import json
from typing import Any, Dict, List, Optional


class DataValidator:
    """Simple helper for validating LLM-generated or user data."""

    def __init__(self, required_fields: List[str], schema: Optional[Dict[str, str]] = None):
        self.required_fields = required_fields
        self.schema = schema or…
14 0 Open
Automation & scripting easy

Pin Python package versions in requirements.txt

Pin package versions in requirements.txt-style text by adding ==version when no specifier is present, while preserving existing version constraints and comments.

requirements automation versions
Python
import re
from pathlib import Path


def pin_versions(requirements_text: str) -> str:
    """
    Pin package versions in requirements.txt-style text.
    Adds ==version if no version specifier is present.
    Keeps existing specifiers (>=, <=, ~=, etc.) unchanged.
    """
    lines = requirements_text.strip().splitli…
14 0 Open
Data pipelines & processing easy

Test a Python Pipeline with Fixture Sample Rows

Test pipeline functions with sample rows provided by a pytest fixture, verifying required keys and value constraints.

pytest fixtures data-pipelines
Python
import pytest


def get_value(data: dict, key: str):
    return data.get(key)


def sample_rows():
    return [
        {"name": "Alice", "age": 30, "city": "London"},
        {"name": "Bob", "age": 25, "city": "Paris"},
        {"name": "Charlie", "age": 35, "city": "Berlin"},
    ]


@pytest.fixture
def sample_data(…
16 0 Open
Database scaling & optimization medium

How to Simulate Colocated Shard Joins in Python

Groups shards by their node and merges co-located shards into a single logical unit, checking capacity constraints.

sharding database distributed-systems
Python
import random
from collections import defaultdict


def simulate_colocated_shards_join(nodes: list[dict], shards: list[dict]) -> dict:
    """
    Simulates the join of co-located shards (on the same node) into a single
    logical shard. Returns the resulting node-to-shard mapping.

    Each node: {'id': str, 'capaci…
11 0 Open
Database scaling & optimization easy

How to Validate Data Before Scaling in Python

A reusable Python helper that validates required fields and constraint checks on data rows before entering a database pipeline, improving data quality and throughput.

validation data-quality scaling
Python
def validate_data(data, required_fields, constraints=None):
    """
    Basic validation helper demonstrating data-quality workflows
    before scaling (catches bad rows early, improves throughput).
    """
    constraints = constraints or {}

    errors = []
    for field in required_fields:
        if field not in d…
15 0 Open
Database scaling & optimization easy

How to enforce a unique index constraint in Python

Mock a database unique index in Python that rejects duplicate rows based on one or more columns.

database unique index constraint
Python
class MockIndex:
    def __init__(self, columns):
        self.columns = columns
        self._values = set()

    def insert(self, row):
        key = tuple(row[col] for col in self.columns)
        if key in self._values:
            raise ValueError(f"Duplicate key {key} for columns {self.columns}")
        self._v…
14 0 Open
Production deployment patterns easy

PodDisruptionBudget minAvailable in Python

Simulate a Kubernetes PodDisruptionBudget check for minAvailable and maxUnavailable constraints with a Python class.

kubernetes pdb simulation
Python
class PodDisruptionBudget:
    def __init__(self, name, min_available=None, max_unavailable=None):
        self.name = name
        self.min_available = min_available
        self.max_unavailable = max_unavailable

    def check_availability(self, ready_pods):
        if self.min_available is not None:
            ret…
11 0 Open

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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.