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A/B testing & experimentation

User bucketing, experiment metrics, statistical comparison, and rollout guardrails.

5 matches

How to Do Random Assignment in Python for A/B Tests

Assign each item to a binary group (0 or 1) with uniform probability using a small reusable function, optionally weighted, for A/B testing mocks.

random ab-testing assignment

Python

import random

def random_assignment_uniform_mock(items, weights=None):
    """Assign each item to a group (0 or 1) with uniform probability."""
    if weights is None:
        # Default: each item independently gets 0 or 1 with 50% probability
        return [random.randint(0, 1) for _ in items]
    # Optional weight…

13 0 Open

A/B testing & experimentation medium

How to Mock Mutual Exclusion for A/B Experiment Groups in Python

Simulate mutual exclusion for experiment groups using a thread-safe lock, ensuring only one member updates the shared counter at a time.

threading mutual-exclusion ab-testing

Python

import threading
import time
import random


class CountingGate:
    """A mock mutual exclusion gate using a lock."""
    def __init__(self):
        self.counter = 0
        self.lock = threading.Lock()

    def enter(self, group_id, member_id):
        with self.lock:
            current = self.counter
            t…

13 0 Open

A/B testing & experimentation medium

How to Mock Sequential Calls in Python with unittest.mock

Use Mock.side_effect to return a different result for each sequential call and verify the call order with assert_has_calls.

mock unittest testing

Python

import unittest
from unittest.mock import Mock

class Service:
    def fetch(self, item_id):
        raise NotImplementedError

def process_items(service, ids):
    results = []
    for item_id in ids:
        result = service.fetch(item_id)
        results.append(result)
    return results

if __name__ == "__main__":…

14 0 Open

A/B testing & experimentation medium

How to Mock Time for Cache TTL Testing in Python

This code demonstrates how to test a cache's TTL expiration logic by mocking time.time with unittest.mock to control the passage of time.

caching ttl unit-testing

Python

import time
from unittest.mock import patch

class ConfigCache:
    def __init__(self, ttl=60):
        self.ttl = ttl
        self._store = {}
        self._timestamps = {}

    def get(self, key):
        if key not in self._store:
            return None
        if time.time() - self._timestamps[key] > self.ttl:
  …

17 0 Open

A/B testing & experimentation easy

How to Mock an Exposure Event Log Record in Python

Generate a realistic exposure event record with UUID, UTC timestamp, and risk level for testing or experimentation.

mocking events testing

Python

import uuid
from datetime import datetime, timezone


def mock_exposure_event(person_id: str, location: str, duration_minutes: int) -> dict:
    return {
        "event_id": str(uuid.uuid4()),
        "person_id": person_id,
        "location": location,
        "duration_minutes": duration_minutes,
        "timestamp…

16 0 Open

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