Reference library

Python Code Samples

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

9 matches
Strings & text easy

How to Sort Text Alphabetically in Python

Sort words or lines alphabetically with case-insensitive ordering while preserving original casing.

sorting text-processing strings
Python
def sort_words(text):
    """Sort words alphabetically (case-insensitive), preserving case."""
    words = text.split()
    return sorted(words, key=str.lower)


def sort_lines(text):
    """Sort lines alphabetically (case-insensitive), preserving case."""
    lines = [line for line in text.splitlines() if line.strip(…
11 0 Open
Strings & text easy

How to Sort Text in Python with a Simple Helper Function

A compact helper function that sorts a list of strings or splits a string into words and sorts them alphabetically, with optional reverse ordering.

sorting strings text-processing
Python
def sort_text(data, reverse=False):
    """
    Sort a list of strings (or a single string split into words) alphabetically.
    """
    if isinstance(data, str):
        words = data.split()
    else:
        words = [str(item) for item in data]
    return sorted(words, reverse=reverse)


if __name__ == "__main__":
 …
11 0 Open
OOP & classes easy

How to Compare Dataclass Instances by Specific Fields in Python

Use @dataclass(order=True) with field(compare=False) to control which fields determine ordering and equality between instances.

dataclasses comparison sorting
Python
from dataclasses import dataclass, field
from typing import Any

@dataclass(order=True)
class Person:
    name: str = field(compare=False)
    age: int
    height_cm: float
    priority: int = field(compare=False, default=0)

    def __repr__(self):
        return f"Person(name={self.name!r}, age={self.age}, height={s…
14 0 Open
OOP & classes easy

How to Implement Rich Comparison Ordering in Python Classes

This code demonstrates how to implement rich comparison operators (like <, <=, >, >=, ==, !=) in a Python class by defining __lt__ and __eq__, enabling sorting and ordering of custom objects.

rich comparison sorting operators
Python
class Task:
    def __init__(self, priority, name):
        self.priority = priority
        self.name = name

    def __lt__(self, other):
        if not isinstance(other, Task):
            return NotImplemented
        return self.priority < other.priority

    def __eq__(self, other):
        if not isinstance(oth…
12 0 Open
Algorithms & data structures easy

Sort list by multiple keys with tuple ordering in Python

Sort a list of dictionaries by multiple criteria — surname, age, then score descending — using a tuple key and negation.

sorting tuples lambda
Python
def sort_multi_key(data):
    # Sorts by surname, then age, then score descending
    return sorted(
        data,
        key=lambda person: (
            person['surname'].lower(),
            person['age'],
            -person['score']  # negative to reverse sort by score
        )
    )


if __name__ == "__main__"…
14 0 Open
Streaming & messaging easy

How to Partition and Order Kafka-Style Messages by Key in Python

Group messages with the same key into ordered buckets using hashing and a defaultdict, mimicking Kafka partition ordering.

streaming partitioning kafka-pattern
Python
from dataclasses import dataclass
from collections import defaultdict

@dataclass
class Message:
    key: str
    content: str

def partition_and_order(messages, num_partitions=3):
    partitions = defaultdict(list)
    for msg in messages:
        partition_id = hash(msg.key) % num_partitions
        partitions[parti…
14 0 Open
ML engineering pipelines easy

How to ordinal encode categorical data in Python with sklearn

Convert job title categories into ordinal numeric labels using sklearn's OrdinalEncoder with explicit ordering.

ordinal-encoding sklearn categorical-data
Python
from sklearn.preprocessing import OrdinalEncoder
import numpy as np

# Mock data: small job title categories with known ordering
data = np.array([
    ["intern"],
    ["junior"],
    ["mid"],
    ["senior"],
    ["lead"]
])

# Define the ordinal order (lowest to highest)
categories = [["intern", "junior", "mid", "seni…
15 0 Open
Database scaling & optimization easy

UUID vs sequential primary key in Python

Simulate and compare UUID vs sequential primary key generation in Python to understand trade-offs in ordering and uniqueness.

uuid primary-key database
Python
import uuid
import time

def create_record_with_uuid(name):
    record_id = uuid.uuid4()
    return {"id": record_id, "name": name}

def create_record_with_sequential_id(name, counter):
    counter += 1
    return {"id": counter, "name": name}

if __name__ == "__main__":
    # Simulate users inserting records
    sequ…
14 0 Open
Production deployment patterns easy

How to Mock a Dockerfile Multi-Stage Build in Python

Simulate a Dockerfile multi-stage build process in Python using dataclasses to validate stage ordering and file availability before you write the real Dockerfile.

dockerfile multi-stage simulation
Python
from dataclasses import dataclass
from pathlib import Path


@dataclass
class BuildStage:
    name: str
    base_image: str
    files: list[str]
    commands: list[str]


def run_build(stage: BuildStage, context_dir: Path):
    print(f"=== Stage: {stage.name} (base: {stage.base_image}) ===")
    for file in stage.file…
14 0 Open

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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.