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Python Code Samples

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180 matches
A/B testing & experimentation easy

Bonferroni Correction in Python

Applies the Bonferroni correction to a list of p-values to control the family-wise error rate when performing multiple comparisons.

statistics p-values multiple-comparisons
Python
import numpy as np

def bonferroni_correction(p_values, alpha=0.05):
    """Apply Bonferroni correction to a list of p-values."""
    n = len(p_values)
    corrected_alpha = alpha / n
    significant = [p < corrected_alpha for p in p_values]
    return corrected_alpha, significant

if __name__ == "__main__":
    # Moc…
18 0 Open
A/B testing & experimentation easy

How to Build a Guardrail Metrics Monitor in Python

This code implements a mock monitor that records metric values, checks them against thresholds, and summarizes pass/alert statistics.

metrics monitoring ab-testing
Python
import random
import time
from collections import defaultdict


class GuardrailMetricsMonitor:
    def __init__(self):
        self.metrics = defaultdict(list)
        self.thresholds = {
            "prompt_toxicity": 0.8,
            "response_length": 500,
            "latency_ms": 1000,
        }

    def record(s…
16 0 Open
A/B testing & experimentation easy

How to Create a Mock That Returns Inverse Counter Values in Python

Builds a Mock whose side_effect returns the inverse (1/count) of each Counter value, defaulting to 0.0 for unseen keys.

mock counter testing
Python
from collections import Counter
from unittest.mock import Mock

def inverse_mock(counter: Counter) -> Mock:
    """
    Return a Mock that mimics the inverse of a Counter:
    each key returns a value representing the inverse of its count.
    The Mock's side_effect maps keys to their inverse counts.
    """
    mock …
14 0 Open
A/B testing & experimentation easy

How to Create a Sticky Consistent Mock with unittest.mock in Python

Shows how to use unittest.mock.patch.object to mock a method consistently across multiple calls, returning a sticky value every time.

unittest mock testing
Python
from unittest.mock import patch

class Database:
    def fetch(self, key):
        return f"real value for {key}"

def get_value(db, key):
    return db.fetch(key)

if __name__ == "__main__":
    db = Database()
    with patch.object(db, "fetch", return_value="sticky value") as mock_fetch:
        result1 = get_value(…
16 0 Open
A/B testing & experimentation easy

How to Define a Mock Primary Metric in Python

Define a mock primary metric object with a name, value, and unit, and serialize it to a dictionary for experimentation and testing.

metrics mock ab-testing
Python
class Metric:
    def __init__(self, name, value, unit=None):
        self.name = name
        self.value = value
        self.unit = unit

    def to_dict(self):
        result = {"name": self.name, "value": self.value}
        if self.unit:
            result["unit"] = self.unit
        return result

    def __repr…
16 0 Open
Database scaling & optimization easy

Hash index equality mock concept in Python

A simple hash index class in Python that stores key-value pairs in buckets and demonstrates basic equality-based lookup.

hash-index hash-table database
Python
class HashIndex:
    def __init__(self):
        self._buckets = {}

    def insert(self, key, value):
        """Insert a key-value pair into the hash index."""
        index = hash(key) % 10
        if index not in self._buckets:
            self._buckets[index] = []
        self._buckets[index].append((key, value))…
13 0 Open
Database scaling & optimization easy

How to Replicate Data Across All Shards in Python

Mocks a global table that replicates a key-value pair to every shard, ensuring reads return the same value from any shard.

sharding replication distributed systems
Python
from dataclasses import dataclass
from typing import Dict, List


@dataclass
class Shard:
    id: str
    data: Dict[str, int]


class GlobalTable:
    def __init__(self, shards: List[Shard]):
        self._shards = {s.id: s for s in shards}

    def set_value(self, key: str, value: int) -> None:
        """Replicate …
15 0 Open
Database scaling & optimization easy

How to Speed Up Column Lookups with DataFrame Index in Python

Use pandas set_index to make repeated column value lookups O(1)-style fast instead of scanning the whole DataFrame each time.

pandas indexing performance
Python
import pandas as pd

# Mock dataset with duplicate customer IDs
data = {"customer_id": [101, 102, 103, 101, 104, 102],
        "order_amount": [250.0, 85.5, 300.0, 175.25, 420.0, 95.75]}

df = pd.DataFrame(data)
df = df.set_index("customer_id")

# Simulated lookup request
search_id = 102

# Fast index-based lookup (no…
16 0 Open
Auth & security at scale easy

Fetch Secrets from a Mock Secrets Manager in Python

Build a minimal in-memory secrets manager that stores and retrieves secret values, raising a KeyError for missing names.

secrets-management security mock
Python
import json

class SecretsManager:
    """Mock secrets manager that returns secrets from a local store."""
    
    def __init__(self, store=None):
        self.store = store or {
            "api_key": "mock-api-key-123",
            "db_password": "s3cret-p@ss",
            "jwt_secret": "dev-only-secret"
        }
…
17 0 Open
Auth & security at scale easy

How to Enforce a Strict Referrer Policy in Python

Validate HTTP headers to enforce a strict same-origin Referrer policy, accepting only origin-only URLs or absent Referer values.

referrer security headers
Python
import re
from unittest.mock import patch

def strict_referrer_policy(headers):
    """Return True if Referer header is absent or strictly same-origin."""
    referer = headers.get("Referer")
    if referer is None:
        return True
    # Strict-Origin-When-Cross-Origin allows same-origin full URL
    # but here we…
16 0 Open
Production deployment patterns easy

How to Build a Data Helper for Production Deployment in Python

Build a reusable DataHelper class that loads configs, validates required keys, normalizes string values, and logs schema details — a production-ready data processing pattern.

json pathlib data-processing
Python
import json
from pathlib import Path
from typing import Any, Dict

class DataHelper:
    """Common data processing patterns for production deployment."""
    
    def __init__(self, config_path: str | Path):
        self.config_path = Path(config_path)
        self.config = self._load_config()
    
    def _load_confi…
15 0 Open
Production deployment patterns easy

How to Merge Helm Chart Values Per Environment in Python

Merge default Helm chart values with environment-specific overrides using a recursive dictionary merge function, then write each environment's YAML file.

helm merge yaml
Python
from pathlib import Path
import json
import tempfile


DEFAULT_VALUES = {
    "image": "nginx:latest",
    "replicas": 1,
    "resources": {"cpu": "100m", "memory": "128Mi"},
}

ENV_OVERRIDES = {
    "dev": {"replicas": 1, "resources": {"cpu": "50m"}},
    "staging": {"replicas": 2, "resources": {"cpu": "250m", "memor…
12 0 Open

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