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Python Code Samples

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

81 matches
API design & gRPC easy

Return Proper HTTP Status Codes Table in Python

Mock HTTP status code table with proper numeric and textual representations, including formatted status lines and a filtered table view.

http-status api mock
Python
# Mock HTTP status code table with proper numeric and textual representations

codes = {
    200: "OK",
    201: "Created",
    204: "No Content",
    301: "Moved Permanently",
    302: "Found",
    304: "Not Modified",
    400: "Bad Request",
    401: "Unauthorized",
    403: "Forbidden",
    404: "Not Found",
    50…
13 0 Open
Streaming & messaging easy

Dedupe processed message IDs in Python

Filters an inbox of messages by removing items whose IDs have already been processed, using a set for fast lookups.

deduplication streaming json
Python
from pathlib import Path
import json


def dedupe_processed_ids(inbox_file: Path, processed_file: Path) -> list:
    processed = set(json.loads(processed_file.read_text()))
    inbox = json.loads(inbox_file.read_text())
    deduped = [item for item in inbox if item["id"] not in processed]
    return deduped


if __nam…
13 0 Open
Caching & Redis easy

How to cache filtered data in Redis with Python

This code caches filtered list results in Redis using an MD5 hash key, returning cached results when available.

redis caching filtering
Python
import redis
import json
import hashlib
import time

cache = redis.Redis(host='localhost', port=6379, db=0, decode_responses=True)

def filter_data(data, predicate_key, predicate_value):
    """Filter a list of dicts by key-value pair, with Redis caching."""
    cache_key = hashlib.md5(
        f"{predicate_key}:{pred…
13 0 Open
Observability & SRE easy

How to Use Log Levels DEBUG INFO WARNING ERROR in Python

Demonstrates Python's logging levels (DEBUG, INFO, WARNING, ERROR) with basicConfig and a logger, showing how severity filtering controls output.

logging log-levels observability
Python
import logging

# Configure a mock logger to demonstrate log levels
logging.basicConfig(level=logging.DEBUG, format="%(levelname)s: %(message)s")
logger = logging.getLogger("mock_logger")

# Simulate events at each severity level
logger.debug("Detailed diagnostic info")
logger.info("General system operation")
logger.w…
13 0 Open
Big data & Spark easy

How to Filter and Project Spark DataFrames with PySpark SQL

Simulate a SQL SELECT with WHERE using PySpark DataFrame select and filter to project columns and apply conditions.

pyspark dataframe filter
Python
from pyspark.sql import SparkSession
from pyspark.sql.functions import col

spark = SparkSession.builder.appName("QueryFilterMock").master("local[2]").getOrCreate()

data = [
    ("Alice", 28, "Engineering"),
    ("Bob", 35, "Sales"),
    ("Carol", 32, "Engineering"),
    ("David", 25, "Marketing"),
    ("Eve", 29, "E…
14 0 Open
Big data & Spark easy

How to Mock Partition Pruning in Python

A dataclass-based mock that filters partitions by year and month to emulate Spark's partition pruning logic.

spark partition dataclass
Python
from dataclasses import dataclass
from typing import List


@dataclass(frozen=True)
class Partition:
    id: int
    year: int
    month: int


class PartitionPruner:
    """Mock partition pruning: only keep partitions that match the filter."""
    def __init__(self, partitions: List[Partition]):
        self._partiti…
15 0 Open
ML engineering pipelines easy

Build a Data Helper Class in Python for ML Pipelines

A beginner-friendly Python class that summarizes, filters, and exports ML dataset rows as JSON.

data-helper ml-pipeline json
Python
from typing import List, Dict, Any
import json

class DataHelper:
    """Beginner-friendly helpers for ML data pipelines."""
    
    def __init__(self, data: List[Dict[str, Any]]):
        self.data = data
        self.keys = list(data[0].keys()) if data else []
    
    def summary(self) -> Dict[str, Any]:
        "…
16 0 Open
Database scaling & optimization easy

Build a Partial Index Mock in Python for Database Filtering

Simulate a partial database index by filtering keys with a predicate, then return a limited mock lookup dictionary.

partial-index database mock
Python
data = [
    "alpha", "beta", "gamma", "delta", "epsilon",
    "zeta", "eta", "theta", "iota", "kappa"
]

filtered_keys = [item for item in data if len(item) >= 5]

def mock_partial_index(keys, filter_func, limit=3):
    result = {}
    for key in keys:
        if not filter_func(key):
            continue
        res…
12 0 Open
Database scaling & optimization easy

How to Create a Data Helper Class in Python for JSON Files

Build a beginner-friendly Python helper class to read, write, filter, and summarize JSON data files with clean, reusable methods.

json data-helper file-io
Python
import json
from pathlib import Path


class DataHelper:
    """Simple beginner-friendly helper for reading and writing JSON data files."""

    @staticmethod
    def read_json(filename):
        file_path = Path(filename)
        if file_path.exists():
            with file_path.open("r", encoding="utf-8") as f:
    …
13 0 Open

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