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Python Code Samples

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

10 matches
Strings & text easy

How to Process Text in Python

This code processes multiline text by splitting lines, stripping whitespace, counting words and characters, and converting to lowercase.

text-processing strings beginner
Python
def process_text(text):
    lines = text.split("\n")
    clean_lines = []
    for line in lines:
        stripped = line.strip()
        if stripped:
            tokens = stripped.split()
            title_case = stripped.lower()
            clean_lines.append({
                "raw": stripped,
                "word_c…
13 0 Open
Lists & loops easy

How to Process Text Lines with Lists and Loops in Python

This code processes a list of text lines by stripping whitespace, converting to uppercase, and reporting character counts per line and totals.

lists loops text-processing
Python
def process_text(lines):
    """Convert a list of text lines to uppercase and report line statistics."""
    processed = []
    total_chars = 0
    
    for index, line in enumerate(lines, start=1):
        cleaned = line.strip().upper()
        processed.append(cleaned)
        total_chars += len(cleaned)
        pri…
13 0 Open
Dictionaries & sets easy

How to Count Word Frequencies in Python with Counter and Sets

This code processes a text string by lowercasing, splitting into words, counting frequencies with Counter, and extracting unique and sorted word lists using sets.

counter sets text-processing
Python
from collections import Counter

def process_text(text):
    words = text.lower().split()
    word_counts = Counter(words)
    unique_words = set(words)
    sorted_words = sorted(unique_words)
    
    return {
        "total_words": len(words),
        "unique_words": len(unique_words),
        "word_frequencies": di…
12 0 Open
Comprehensions & generators easy

Memory efficient map over large file in Python

A generator-based streaming map that processes a large file line by line without loading the whole file into memory.

generator file-io streaming
Python
import sys

def process_lines(file_path):
    """Memory-efficient map over a large file: yields processed lines."""
    with open(file_path, 'r') as f:
        for line in f:
            # Example mapping: strip whitespace and uppercase
            yield line.strip().upper()

if __name__ == "__main__":
    # Use a sma…
13 0 Open
Automation & scripting easy

How to Build a CLI with argparse in Python

Create a beginner-friendly command-line tool in Python that processes multiple filenames with optional flags for verbose output and uppercase conversion.

argparse cli scripting
Python
import argparse

def main():
    parser = argparse.ArgumentParser(
        description="A simple CLI to process files with optional verbose mode."
    )
    parser.add_argument("filenames", nargs="+", help="Files to process")
    parser.add_argument("-v", "--verbose", action="store_true", help="Print extra details")
 …
12 0 Open
Automation & scripting easy

How to Kill Zombie Processes Matching a Name in Python

Scans running processes with ps, finds zombies whose command name matches a pattern, and attempts to kill them with SIGKILL.

subprocess process automation
Python
import subprocess
import re
import signal


def find_zombies(name_pattern):
    """Find PIDs of zombie processes matching the given pattern."""
    result = subprocess.run(["ps", "-eo", "pid,stat,comm"], capture_output=True, text=True)
    zombies = []
    for line in result.stdout.splitlines()[1:]:  # Skip header
   …
11 0 Open
Concurrency & performance easy

How to Send and Receive Messages Between Processes with multiprocessing.Pipe in Python

Use multiprocessing.Pipe to create a two-way connection between two processes, send a message from parent to child, and receive a reply back.

multiprocessing pipe interprocess-communication
Python
import multiprocessing


def child_process(conn):
    """Receive from parent and send back a response."""
    message = conn.recv()
    print(f"Child received: {message}")
    conn.send("Hello from child!")


if __name__ == "__main__":
    parent_conn, child_conn = multiprocessing.Pipe()

    process = multiprocessing…
14 0 Open
Concurrency & performance easy

How to Use pool.map for CPU-Bound Tasks in Python

Distribute CPU-intensive functions across processes with multiprocessing.Pool.map and measure the performance gain.

multiprocessing pool cpu-bound
Python
from multiprocessing import Pool
import time

def cpu_bound_task(n):
    """Mock CPU-bound work: compute sum of squares."""
    total = 0
    for i in range(n):
        total += i * i
    return total

if __name__ == "__main__":
    numbers = [10_000_000, 12_000_000, 8_000_000, 15_000_000]

    start = time.perf_count…
11 0 Open
Concurrency & performance easy

How to spawn multiple worker processes in Python with multiprocessing.Process

Spawns three separate worker processes using multiprocessing.Process, runs them concurrently, and waits for all to finish before printing a completion message.

multiprocessing parallel concurrency
Python
import multiprocessing
import time

def worker(name):
    print(f"Worker {name} started")
    time.sleep(1)
    print(f"Worker {name} finished")
    return name

if __name__ == "__main__":
    processes = []
    for i in range(3):
        p = multiprocessing.Process(target=worker, args=(i,))
        processes.append(p…
14 0 Open
Reliability & rate limiting easy

How to implement an idempotency key store in Python

Build an in-memory idempotency key store with TTL that processes a request once and reuses the cached result for duplicate calls.

idempotency cache ttl
Python
import hashlib
import time
from typing import Dict, Optional


class IdempotencyStore:
    """Simple in-memory idempotency key store with mock processing."""

    def __init__(self, ttl_seconds: int = 3600) -> None:
        self.ttl = ttl_seconds
        self._store: Dict[str, tuple[str, float]] = {}

    def _is_expi…
15 0 Open

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Samples are quick reference — one concept per page. For step-by-step teaching, use our Python tutorials. To test yourself, try quizzes or coding challenges. Clean up style with the Python formatter.