Reference library

Python Code Samples

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

2 matches
System design patterns easy

Route Messages to Handlers with a Python Dict

This code demonstrates a simple message routing pattern using a dictionary to map topic keys to handler functions, with a default handler for unmatched topics.

routing dictionary message-broker
Python
def route_message(message, routing_table):
    """Route a message to the correct handler based on the topic key."""
    topic = message.get("topic", "default")
    handler = routing_table.get(topic, routing_table.get("default"))
    return handler(message)


def handle_orders(message):
    return f"Orders handler proc…
12 0 Open
Streaming & messaging medium

In-Memory PubSub Topic Subscribe Mock in Python

Build a thread-safe in-memory publish/subscribe mock where handlers subscribe to named topics and receive every message published to them.

pubsub mock events
Python
class PubSub:
    def __init__(self):
        self.topics = {}

    def subscribe(self, topic, callback):
        if topic not in self.topics:
            self.topics[topic] = []
        self.topics[topic].append(callback)

    def publish(self, topic, message):
        for callback in self.topics.get(topic, []):
    …
16 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.