Reference library

Python Code Samples

Easy snippets you can copy, study, and run in the browser editor.

6 matches
Lists & loops easy

Separate Evens and Odds into Two Lists in Python

Split a list of numbers into two lists containing even and odd numbers using a simple loop and the modulo operator.

lists loops modulo
Python
def separate_evens_odds(numbers):
    evens = []
    odds = []
    for num in numbers:
        if num % 2 == 0:
            evens.append(num)
        else:
            odds.append(num)
    return evens, odds

if __name__ == "__main__":
    nums = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
    evens, odds = separate_evens_odds(nu…
13 0 Open
Algorithms & data structures easy

How to partition a list into n nearly equal parts in Python

Divide a list into n contiguous chunks of nearly equal size using an average-length calculation that distributes the remainder evenly.

partitioning chunks slicing
Python
def partition(lst, n):
    """Partition a list into n nearly equal contiguous parts."""
    if n <= 0:
        raise ValueError("n must be positive")
    if not lst:
        return [[] for _ in range(n)]
    
    parts = []
    avg = len(lst) / n
    last_idx = 0.0
    
    while last_idx < len(lst):
        end_idx =…
14 0 Open
Data pipelines & processing easy

How to Partition Output Files by Date Key in Python

Group output files into a dictionary partitioned by a YYYYMMDD date key extracted from the filename prefix.

file-partitioning date-key pathlib
Python
from pathlib import Path
from collections import defaultdict

def partition_files_by_date(directory: str) -> dict:
    """Partition output files by date key extracted from filename (YYYYMMDD prefix)."""
    path = Path(directory)
    partitions = defaultdict(list)
    
    for file in path.iterdir():
        if file.i…
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
Big data & Spark easy

Partition Data by Hash Key Mod N in Python

Returns a partition index for a string key by hashing it with MD5 and taking modulo N, then groups sample keys into partitions.

hashing partitioning hashlib
Python
import hashlib


def partition_key(key: str, num_partitions: int) -> int:
    """Return partition index for key using MD5 hash mod N."""
    digest = hashlib.md5(key.encode()).hexdigest()
    return int(digest, 16) % num_partitions


if __name__ == "__main__":
    keys = ["alice", "bob", "carol", "dave", "eve"]
    nu…
12 0 Open
Database scaling & optimization easy

How to mock directory-based sharding in Python

Simulates distributing files into logical shards using a deterministic hash of each filename, mocking how a database might shard rows across nodes.

sharding hash partitioning
Python
import os
import hashlib
from collections import defaultdict
from pathlib import Path


def get_shard_for_key(key: str, num_shards: int) -> int:
    """Return a deterministic shard index (0..num_shards-1) for a key."""
    digest = hashlib.md5(key.encode('utf-8')).hexdigest()
    return int(digest, 16) % num_shards


…
14 0 Open

Browse by section

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.