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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.
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…
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.
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…
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.
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 …
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.
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(…
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.
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…
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.
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))…
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.
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 …
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.
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…
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.
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"
}
…
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.
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…
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.
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…
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.
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…
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