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Python Code Samples

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128 matches
Big data & Spark easy

How to Implement MapReduce Word Count in Python Using a Dict

Simulate a MapReduce word count pipeline in Python with a mock dict, splitting text into words, shuffling, and reducing to frequency counts.

mapreduce word-count dictionary
Python
def map_reduce_word_count(text: str) -> dict:
    """Simulate a MapReduce pipeline to count word frequencies."""
    # MAP phase: split into words and emit (word, 1) pairs
    mapped = []
    for word in text.lower().split():
        # Clean word of punctuation
        clean_word = ''.join(char for char in word if cha…
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 …
13 0 Open
A/B testing & experimentation easy

Simulate a Ramp Rollout Percentage in Python

Simulates a percentage-based ramp rollout with deterministic seeding, returning success/failure/in-progress counts for a mock user population.

rollout simulation random
Python
import random
from enum import Enum

class RolloutStatus(Enum):
    SUCCESS = "success"
    FAILED = "failed"
    IN_PROGRESS = "in_progress"

def simulate_ramp_rollout(total_users: int, percentage: int, seed: int = 42) -> dict:
    """
    Simulates a mock ramp rollout for a given percentage of users.
    Returns sta…
14 0 Open
Database scaling & optimization easy

How to Count Star vs Estimate Matches in Python

Count how many times 'star' and 'estimate' annotations match their actual labels in a list of mock comparison results.

counting dictionary matching
Python
def count_star_vs_estimate(mock_scores):
    """
    Count the number of times 'star' wins and 'estimate' wins
    from a list of mock comparison results.

    Args:
        mock_scores: list of tuples, each (annotation, actual)
                     where annotation is 'star' or 'estimate'

    Returns:
        dict w…
12 0 Open
Database scaling & optimization easy

How to Mock a Function Call in Python with unittest.mock

Use unittest.mock.Mock to wrap a function and spy on its call count and arguments in Python.

mock unittest spy
Python
import random
from unittest.mock import Mock, patch


def select_n_plus_one(numbers: list[int]) -> int:
    """Return the first number that appears more than once, if any."""
    seen = set()
    for num in numbers:
        if num in seen:
            return num
        seen.add(num)
    return -1


def detect_mock(se…
14 0 Open
Database scaling & optimization easy

How to Shard Data by User ID Hash in Python

Deterministically map user IDs to shard indexes using an MD5 hash modulo the shard count in Python.

sharding hashing md5
Python
import hashlib

def shard_id(user_id: str, num_shards: int = 4) -> int:
    """Deterministically map a user_id to a shard index using MD5."""
    digest = hashlib.md5(user_id.encode("utf-8")).hexdigest()
    return int(digest[:8], 16) % num_shards

if __name__ == "__main__":
    user_ids = ["alice", "bob", "carol", "d…
12 0 Open
Production deployment patterns easy

How to Attach an SBOM to a Release in Python (Mock)

A mock function that attaches a Software Bill of Materials (SBOM) to a GitHub-style release by counting its components and marking the upload as attached.

sbom release json
Python
import json
from pathlib import Path


def attach_sbom_mock(sbom_path: Path, release_tag: str, artifact_name: str) -> dict:
    """Mock attaching an SBOM to a release, returning the simulated upload result."""
    sbom = json.loads(sbom_path.read_text())
    return {
        "release_tag": release_tag,
        "artifa…
14 0 Open
Production deployment patterns easy

How to Mock a Kubernetes Rolling Update with maxSurge in Python

Simulate a Kubernetes rolling update with maxSurge policy, tracking peak and final replica counts during roll transitions.

kubernetes rolling-update maxsurge
Python
from collections import deque

class RollingUpdateMaxSurge:
    def __init__(self, replicas, max_surge):
        self.replicas = replicas
        self.max_surge = max_surge
        self.available = replicas
        self.history = deque()

    def roll(self, desired_replicas):
        """
        Simulate a rolling upd…
13 0 Open

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