Reference library

Python Code Samples

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

33 matches
Reliability & rate limiting easy

Rate Limit per User ID in Python with a Dict Mock

Implements a simple sliding window rate limiter using a defaultdict of timestamps per user ID, blocking requests that exceed a max count within a time window.

rate-limiting defaultdict sliding-window
Python
import time
from collections import defaultdict


class RateLimiter:
    def __init__(self, max_requests, window_seconds):
        self.max_requests = max_requests
        self.window_seconds = window_seconds
        self.user_timestamps = defaultdict(list)

    def allow_request(self, user_id):
        now = time.tim…
14 0 Open
Reliability & rate limiting easy

Rate Limiting with a Simple Python RateLimiter Class

A beginner-friendly Python rate limiter that tracks call timestamps and enforces a maximum number of calls within a rolling time window, with a helper to validate positive integers.

rate-limiting time api
Python
import time

class RateLimiter:
    def __init__(self, max_calls, period_seconds):
        self.max_calls = max_calls
        self.period_seconds = period_seconds
        self.calls = []

    def is_allowed(self):
        now = time.time()
        while self.calls and now - self.calls[0] >= self.period_seconds:
      …
13 0 Open
Observability & SRE easy

Check if a Timestamp Falls in a Daily Maintenance Window in Python

A small Python function that returns True when a datetime falls inside a daily maintenance window, and a demo printing yes/no for sample timestamps.

maintenance datetime scheduling
Python
from datetime import datetime, timedelta
from zoneinfo import ZoneInfo


def in_maintenance_window(now: datetime, start_hour: int = 2, duration_hours: int = 4) -> bool:
    """Return True if 'now' falls inside the daily maintenance window."""
    day_start = now.replace(hour=start_hour, minute=0, second=0, microsecond…
15 0 Open
Observability & SRE easy

Generate Synthetic CPU Utilization Metrics in Python

Creates realistic time-series CPU utilization samples with timestamps, noise, and output as structured JSON for observability demos and testing.

observability metrics time-series
Python
from datetime import datetime, timedelta
import random
import json


def generate_metric_samples(base_value, noise, count=60, interval_minutes=1):
    """Generate realistic CPU utilization samples for a given time window."""
    timestamps = []
    values = []

    now = datetime.utcnow()
    start_time = now - timede…
14 0 Open
Microservices patterns easy

How to Implement an Exactly-Once Deduplication Store in Python

Implement a Python class that deduplicates keys exactly once, tracking first-seen timestamps and duplicate counts.

deduplication exactly-once set
Python
from datetime import datetime
from typing import Any, Hashable


class ExactlyOnceStore:
    def __init__(self) -> None:
        self._seen: set[Hashable] = set()
        self._first_seen: dict[Hashable, datetime] = {}
        self._counts: dict[Hashable, int] = {}

    def add(self, key: Hashable, value: Any = None) …
13 0 Open
Big data & Spark easy

Session window gap mock in Python

Group sorted timestamps into sessions where any gap between consecutive events exceeds a threshold starts a new session.

timestamps sessions windowing
Python
from datetime import datetime, timedelta


def session_windows(timestamps, gap_seconds=300):
    """Group timestamps into sessions where gaps > gap_seconds start new sessions."""
    if not timestamps:
        return []

    # Sort timestamps chronologically to ensure correct windowing
    timestamps = sorted(timestam…
14 0 Open
ML engineering pipelines easy

How to Generate Experiment Tracking Run IDs in Python

Generate unique experiment run IDs with timestamps and random suffixes for tracking ML pipeline executions.

run-ids experiment-tracking ml-pipelines
Python
import random
import string
import time

def generate_run_id(prefix="exp"):
    timestamp = time.strftime("%Y%m%d_%H%M%S")
    suffix = "".join(random.choices(string.ascii_lowercase + string.digits, k=6))
    return f"{prefix}_{timestamp}_{suffix}"

if __name__ == "__main__":
    # Simulate tracking three experiment r…
13 0 Open
ML engineering pipelines easy

How to Mock a Feature Store Online Lookup in Python

This code simulates an online feature store with single and batch retrieval methods, using a dict-backed cache and timestamps.

feature-store ml-infrastructure online-lookup
Python
import random
import time


class OnlineFeatureStore:
    def __init__(self):
        self.features = {}

    def put(self, entity_id: str, feature_name: str, value):
        key = (entity_id, feature_name)
        self.features[key] = (value, time.time())

    def get(self, entity_id: str, feature_name: str):
       …
13 0 Open
A/B testing & experimentation easy

How to Mock a Remote Config Fetch in Python

Simulate a remote config API response with metadata, timestamps, and mock data for testing or local development.

mock config testing
Python
import json
from datetime import datetime
from typing import Any, Dict

def fetch_remote_config(mock_data: Dict[str, Any]) -> Dict[str, Any]:
    """Simulate fetching a remote config with metadata and timestamps."""
    return {
        "status": "success",
        "source": "mock",
        "fetched_at": datetime.utcn…
14 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.