Reference library

Python Code Samples

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

3 matches
Files & data easy

Build a Simple ETL Pipeline in Python

A simple ETL pipeline that reads JSON Lines, transforms records with filtering and normalization, and writes the result to JSON.

etl json jsonl
Python 
import json
from pathlib import Path


def read_input(file_path: Path) -> list[dict]:
    """Read JSON lines file into list of dicts."""
    with file_path.open("r", encoding="utf-8") as f:
        return [json.loads(line) for line in f if line.strip()]


def transform(records: list[dict]) -> list[dict]:
    """Transf…
13 0 Open
AI & LLM integration patterns easy

How to Log Prompts and Completions as JSONL Audit Files in Python

Read a JSONL file of LLM prompt–completion pairs, compute totals and averages, then write an audit summary with timestamps.

jsonl audit llm
Python 
import json
from pathlib import Path
from datetime import datetime


def audit_jsonl(filepath):
    logs = []
    with open(filepath, encoding="utf-8") as f:
        for line in f:
            line = line.strip()
            if not line:
                continue
            entry = json.loads(line)
            logs.ap…
15 0 Open
Data pipelines & processing medium

How to Stream a Large JSONL File Line by Line in Python

Process a large JSON-lines file incrementally using streaming techniques to avoid loading the entire file into memory.

streaming jsonl large-files
Python 
import json

def process_large_file(filepath, chunk_size=8192):
    """
    Stream a large JSON-lines file line by line, processing each record
    without loading the entire file into memory.
    """
    total_count = 0
    total_sum = 0
    
    with open(filepath, 'r') as f:
        while True:
            chunk = …
13 0 Open

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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.

Related coding tools

Free online Python IDE Write and run Python in your browser — no install. Free Python code formatter Format with autopep8 — side-by-side PEP 8 cleanup.