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Python Code Samples

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

12 matches
Lists & loops easy

How to Normalize a List of Numbers in Python

This Python function normalizes a list of numeric values to the range [0, 1] using min-max scaling, returning a new list and leaving the original unchanged.

lists loops normalization
Python
def normalize(data):
    """
    Normalize a list of numeric values to the range [0, 1].
    Returns a new list, leaving the original unchanged.
    """
    if not data:
        return []
    
    min_val = min(data)
    max_val = max(data)
    
    # Handle the edge case where all values are identical
    if min_val …
17 0 Open
Lists & loops easy

How to Normalize a List of Numbers to the 0-1 Range in Python

Scale a list of numbers so the minimum becomes 0 and the maximum becomes 1 using min-max normalization.

normalization lists data-science
Python
def min_max_normalize(values):
    """Normalize a list of numbers to the [0, 1] range."""
    if not values:
        return []
    min_val = min(values)
    max_val = max(values)
    if min_val == max_val:
        return [0.0] * len(values)
    return [(x - min_val) / (max_val - min_val) for x in values]


if __name__…
12 0 Open
Cloud + Python easy

How to Mock Auto Scaling Policy Scale Out in Python

Define a mock auto-scaling function that scales out capacity by a factor up to a max, simulating AWS-like events.

auto-scaling cloud simulation
Python
def mock_scale_out(current_capacity: int, max_capacity: int, scale_factor: int = 1) -> tuple:
    """
    Mock auto-scaling policy: scales out by the specified factor
    if capacity allows, capped at max_capacity.
    """
    if current_capacity >= max_capacity:
        return current_capacity, False
    
    new_cap…
14 0 Open
ML engineering pipelines medium

How to Build an sklearn Pipeline with ColumnTransformer in Python

A mock example showing how to chain preprocessing and a regression model into a single sklearn Pipeline, scaling numeric features and one-hot encoding categorical features with ColumnTransformer.

sklearn pipeline columntransformer
Python
import numpy as np
from sklearn.compose import ColumnTransformer
from sklearn.preprocessing import StandardScaler, OneHotEncoder
from sklearn.pipeline import Pipeline
from sklearn.linear_model import LinearRegression

# Mock dataset
X = np.array([[1, 'red'], [2, 'blue'], [3, 'red'], [4, 'green'], [5, 'blue']], dtype=o…
13 0 Open
ML engineering pipelines easy

StandardScaler mock in Python

A pure-Python StandarScaler class that standardizes features to zero mean and unit variance without sklearn.

scaling preprocessing machine-learning
Python
import math

class StandardScaler:
    def __init__(self):
        self.mean_ = None
        self.std_ = None

    def fit(self, X):
        n = len(X)
        self.mean_ = [sum(col) / n for col in zip(*X)]
        self.std_ = []
        for col in zip(*X):
            variance = sum((x - self.mean_[i]) ** 2 for i, x …
12 0 Open
Database scaling & optimization medium

Database Helper in Python with SQLite Scaling Optimization

Build a beginner-friendly SQLite database helper class with WAL, indexed queries, and efficient batch inserts for scaling.

sqlite database scalability
Python
import sqlite3
from contextlib import contextmanager


class DatabaseHelper:
    """Beginner-friendly helper for SQLite database operations with scaling tips."""

    def __init__(self, db_path):
        self.db_path = db_path

    @contextmanager
    def connection(self):
        """Context manager for automatic comm…
14 0 Open
Database scaling & optimization easy

How to Convert Data with Scaling for Database Optimization in Python

A beginner-friendly helper that normalizes and scales numeric fields in a list of dicts, reducing storage footprint for database efficiency.

data conversion database scaling
Python
import json
from datetime import datetime

def convert_data(data: list[dict], scale_factor: int = 1) -> list[dict]:
    """Convert a list of dicts to a scaled, normalized format for database efficiency."""
    converted = []
    for row in data:
        normalized = {}
        for key, value in row.items():
          …
14 0 Open
Database scaling & optimization medium

How to Mock a Hot Shard Split in Python

Simulate a database hot shard splitting into two shards by key ranges when it exceeds a threshold, with a mock class for testing.

sharding databases mock
Python
import random
from collections import defaultdict


class HotShardMock:
    """Mock implementation of a hot shard split in a distributed database."""

    def __init__(self, shard_id="shard_1", max_entries=5):
        self.shard_id = shard_id
        self.max_entries = max_entries
        self.entries = {}

    def ad…
16 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 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
Database scaling & optimization medium

Simulate Shard Key Cardinality in Python

Generate mock data with configurable cardinality to evaluate shard key distribution and detect hotspots in database scaling design.

sharding cardinality database
Python
import random
import string

def calculate_cardinality(values):
    """Return the number of distinct values in the given list."""
    return len(set(values))

def generate_mock_data(num_records, cardinality):
    """Generate mock records for a shard key with given cardinality."""
    possible_keys = [f"key_{i:04d}" fo…
17 0 Open
Production deployment patterns medium

Mock Kubernetes HPA CPU Scaling in Python

Python function that simulates CPU utilization and calculates desired replicas using the Kubernetes HPA formula.

kubernetes hpa autoscaling
Python
import random
import time


def simulate_cpu_utilization(target_utilization=50, samples=10):
    """Simulate CPU utilization readings for HPA mock."""
    utilizations = []
    for _ in range(samples):
        # Simulate fluctuating CPU with random noise around target
        current = target_utilization + random.unif…
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.