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A/B testing & experimentation

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

3 matches

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 …

13 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(…

15 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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