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Python Code Samples

Medium snippets you can copy, study, and run in the browser editor.

7 matches
OOP & classes medium

How to Create a Data Splitter Class in Python

This code defines a DataSplitter class that splits data by index, into chunks, or by a predicate, demonstrating OOP principles in Python.

class data-splitting slicing
Python
class DataSplitter:
    def __init__(self, data):
        self.data = list(data)
    
    def split_by_index(self, index):
        return self.data[:index], self.data[index:]
    
    def split_into_chunks(self, chunk_size):
        return [self.data[i:i + chunk_size] for i in range(0, len(self.data), chunk_size)]
   …
14 0 Open
Algorithms & data structures medium

Split Array Largest Sum in Python (Minimize Largest Subarray Sum)

Binary search + greedy check to split an array into k subarrays while minimizing the largest subarray sum.

binary-search greedy array
Python
def can_split(nums, k, max_sum):
    subarrays = 1
    current_sum = 0
    for num in nums:
        if current_sum + num <= max_sum:
            current_sum += num
        else:
            subarrays += 1
            current_sum = num
            if subarrays > k:
                return False
    return True

def spli…
15 0 Open
System design patterns medium

How to Implement CQRS with Separate Read and Write Models in Python

Implements Command Query Responsibility Segregation (CQRS) by splitting data into separate write and read models with dedicated repositories, using dataclasses for structure.

cqrs dataclasses repositories
Python
from dataclasses import dataclass, field
from typing import List, Dict, Optional


@dataclass
class OrderWriteModel:
    order_id: int
    customer: str
    items: List[str] = field(default_factory=list)

    def add_item(self, item: str) -> None:
        self.items.append(item)


@dataclass
class OrderReadModel:
    …
14 0 Open
ML engineering pipelines medium

K-Fold Cross Validation in Python: A Simple Implementation

Implements k-fold cross validation from scratch, splitting data into folds and computing MSE scores for a baseline mean-predictor model.

cross-validation ml model-evaluation
Python
import random
from statistics import mean


def cross_validation_scores(data, labels, k=5, seed=42):
    random.seed(seed)
    indices = list(range(len(data)))
    random.shuffle(indices)
    fold_size = len(indices) // k
    folds = []
    for i in range(k):
        if i == k - 1:
            folds.append(indices[i *…
16 0 Open
Database scaling & optimization medium

How to Mock a Hot Shard Split in Python

Simulate a database hot shard splitting into two shards by key ranges when it exceeds a threshold, with a mock class for testing.

sharding databases mock
Python
import random
from collections import defaultdict


class HotShardMock:
    """Mock implementation of a hot shard split in a distributed database."""

    def __init__(self, shard_id="shard_1", max_entries=5):
        self.shard_id = shard_id
        self.max_entries = max_entries
        self.entries = {}

    def ad…
16 0 Open
Database scaling & optimization medium

Mock CQRS Read/Write Split in Python

Separate order mutations from queries using a read model and write model to mock CQRS-style separation of concerns.

cqrs read-write dataclass
Python
from dataclasses import dataclass, field
from typing import List, Dict


@dataclass
class Order:
    id: int
    amount: float
    status: str = "pending"


class OrderWriteModel:
    """Handles all mutations (writes) to orders."""

    def __init__(self):
        self._orders: Dict[int, Order] = {}
        self._next…
12 0 Open
Production deployment patterns medium

How to Mock Canary Deployment Traffic Split in Python

Simulate a canary deployment's stable/canary traffic split using deterministic request hashing to mock rollout behavior with precise percentage control.

canary-deployment traffic-split simulation
Python
class CanaryDeployment:
    def __init__(self, stable_weight: float = 0.9, canary_weight: float = 0.1):
        self.stable_weight = stable_weight
        self.canary_weight = canary_weight
        self.total_weight = stable_weight + canary_weight

    def route_request(self, request_id: int) -> str:
        """Route …
14 0 Open

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