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Python Code Samples

Copy-ready Python snippets by topic and difficulty — short, focused, and runnable in the browser editor.

10 matches
Files & data medium

Build a Personal Work Hours Tracker in Python

A Python class that logs daily work hours to a CSV file and produces a weekly summary of total hours worked.

work-hours time-tracking csv
Python
import csv
from pathlib import Path
from datetime import datetime, date

class WorkHoursTracker:
    def __init__(self, file_path="work_hours.csv"):
        self.file_path = Path(file_path)
        if not self.file_path.exists():
            with open(self.file_path, "w", newline="") as f:
                writer = csv…
29 0 Open
Files & data easy

Convert CSV Files to JSON in Python

Convert a CSV file to a JSON file using Python's built-in csv and json modules.

csv json conversion
Python
import csv
import json

def csv_to_json(csv_filepath, json_filepath):
    """Convert a CSV file to a JSON file."""
    with open(csv_filepath, mode='r', newline='') as csv_file:
        reader = csv.DictReader(csv_file)
        data = [row for row in reader]

    with open(json_filepath, mode='w') as json_file:
      …
43 0 Open
Files & data easy

Detect Outliers in CSV Data Using Z-Score in Python

Read a CSV file and detect outliers in a numeric column by computing z-scores, flagging those exceeding a given threshold — no machine learning required.

outlier-detection z-score csv
Python
import csv
import statistics
from math import sqrt

def detect_outliers(csv_path, column_name, threshold=2.0):
    """Detect outliers in a numeric column using z-score method."""
    values = []
    with open(csv_path, 'r', newline='') as f:
        reader = csv.DictReader(f)
        if column_name not in reader.field…
19 0 Open
Files & data medium

How to Build a CSV Comparison Tool That Highlights Every Changed Cell in Python

Read two CSV files with DictReader, compare cell by cell, and return a list of dictionaries describing each changed cell using only the standard library.

csv comparison diff
Python
import csv
from pathlib import Path

def csv_cell_diff(file_a: str, file_b: str) -> list[dict]:
    rows_a = list(csv.DictReader(Path(file_a).open('r', newline='')))
    rows_b = list(csv.DictReader(Path(file_b).open('r', newline='')))
    if not rows_a or not rows_b:
        return []
    columns = list(rows_a[0].key…
20 0 Open
Files & data medium

How to Generate an Inventory Report of All Files in Python

Walk a directory tree, collect metadata for every file, and write a CSV inventory report using Python's os, pathlib, and csv modules.

os.walk pathlib csv
Python
import os
import csv
from pathlib import Path
from datetime import datetime

def generate_inventory_report(root_dir: str = "/", output_file: str = "inventory_report.csv"):
    headers = ["File Path", "Size (bytes)", "Last Modified", "File Type"]
    rows = []
    start_time = datetime.now()
    
    for dirpath, dirna…
28 0 Open
Files & data medium

Scrape HTML Tables and Convert Them to CSV Using Beautiful Soup in Python

Scrape a Wikipedia table with Beautiful Soup and write the data to a CSV file using the csv module.

web scraping beautiful soup csv
Python
import requests
from bs4 import BeautifulSoup
import csv

url = "https://en.wikipedia.org/wiki/List_of_countries_by_GDP_(nominal)"
response = requests.get(url)
soup = BeautifulSoup(response.text, 'html.parser')

tables = soup.find_all('table', {'class': 'wikitable'})

if tables:
    target_table = tables[2]
    rows =…
27 0 Open
Files & data easy

Split CSV Files into Smaller Chunks in Python

Splits a large CSV file into multiple smaller chunk files, preserving the header row in each chunk.

csv file-splitting batch-processing
Python
import csv
import os

def split_csv(input_file, chunk_size=1000, output_prefix="chunk"):
    """Split a large CSV file into smaller chunks."""
    with open(input_file, 'r', newline='') as infile:
        reader = csv.reader(infile)
        header = next(reader)
        
        file_count = 1
        row_count = 0
  …
23 0 Open
Automation & scripting medium

Automatically Generate Charts from CSV Files with One Command

Read a CSV file with headers, extract the first two numeric columns, and save a matplotlib line chart as a PNG image.

csv matplotlib charting
Python
import csv
import sys
from pathlib import Path
import matplotlib.pyplot as plt

def generate_chart(csv_path: str) -> None:
    """Read a CSV file with headers and plot the first two numeric columns."""
    data = []
    with open(csv_path, 'r', newline='') as f:
        reader = csv.reader(f)
        headers = next(re…
38 0 Open
Automation & scripting easy

Automatically Log CPU, RAM, and Disk Usage Every Minute in Python

This script logs CPU, RAM, and disk usage to a CSV file every 60 seconds using psutil and Python's standard library.

psutil automation monitoring
Python
import psutil
import time
import csv
from pathlib import Path

LOG_FILE = Path("system_usage_log.csv")
INTERVAL_SECONDS = 60

def log_system_usage():
    """Write CPU, RAM, and disk usage to CSV every minute."""
    file_exists = LOG_FILE.exists()
    with open(LOG_FILE, mode="a", newline="") as f:
        writer = cs…
24 0 Open
Automation & scripting medium

Build a Complete Web Scraper with Requests and BeautifulSoup in Python

Scrape multiple paginated pages from a website using Requests and BeautifulSoup, with retry logic, error handling, and CSV export.

web scraping requests beautifulsoup
Python
import requests
from bs4 import BeautifulSoup
import csv
import time
from typing import List, Dict, Optional

class WebScraper:
    def __init__(self, base_url: str, output_file: str = "scraped_data.csv"):
        self.base_url = base_url
        self.output_file = output_file
        self.session = requests.Session()…
52 0 Open

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Guide: free Python code samples library

Copy-ready Python snippets for learners and developers

PythonSkillset code samples are short, focused examples organised by topic and difficulty. Every snippet is server-rendered HTML — readable by search engines and easy to copy. Open any sample, read the notes, copy the code, then press Try in editor to run it in the browser with Pyodide.

How to use this library

  1. Pick a topic section — strings, lists, files, functions, and more
  2. Open a sample, read How it works, and copy the code block
  3. Run it in the IDE, tweak values, then take a related quiz or tutorial lesson

Samples vs tutorials and challenges

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.