Reference library

Files & data

Read and write files safely; parse JSON, CSV, and common text formats.

36 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…
60 0 Open
Files & data medium

Build a Secure Local Password Vault with Encrypted Storage in Python

A Python class that stores and retrieves passwords in an encrypted JSON file using Fernet symmetric encryption from the cryptography library.

encryption security passwords
Python
import json
import os
import base64
import hashlib
from cryptography.fernet import Fernet
from getpass import getpass

class PasswordVault:
    def __init__(self, vault_file="vault.json", key_file="vault.key"):
        self.vault_file = vault_file
        self.key_file = key_file
        self.key = self._load_or_creat…
48 0 Open
Files & data medium

Calculate Working Hours Between Two Dates in Python

Compute total business hours (Mon-Fri, 09:00-17:00) between two datetime objects, excluding weekends and non-working hours.

datetime working hours business hours
Python
from datetime import datetime, timedelta

def work_hours_between(start: datetime, end: datetime) -> float:
    """Calculate total working hours between two datetimes (Mon-Fri, 09:00-17:00)."""
    def is_workday(d: datetime) -> bool:
        return d.weekday() < 5
    
    total_hours = 0.0
    current = start
    whi…
48 0 Open
Files & data medium

Chunk Large File Upload Simulation by Blocks in Python

A Python script reads a large binary file in fixed-size chunks and simulates a block-by-block upload with per-chunk SHA256 hashing.

file i/o chunking hashing
Python
import os
import hashlib
from pathlib import Path


def read_file_in_chunks(file_path, chunk_size=8196):
    """Yield chunks of a file as bytes."""
    with open(file_path, 'rb') as f:
        while chunk := f.read(chunk_size):
            yield chunk


def simulate_chunked_upload(file_path, chunk_size=8196):
    """S…
15 0 Open
Files & data medium

Convert Image to ASCII Art in Python

Convert any image to ASCII art by resizing, converting to grayscale, and mapping pixel brightness to characters using Pillow.

image ascii-art pillow
Python
from PIL import Image
import sys

ASCII_CHARS = "@%#*+=-:. "

def resize_image(image, new_width=100):
    """Resize image maintaining aspect ratio."""
    width, height = image.size
    ratio = height / width
    new_height = int(new_width * ratio * 0.55)  # 0.55 adjusts for font aspect ratio
    return image.resize((…
51 0 Open
Files & data medium

Create a Local File Versioning System Using Pure Python

Track file changes locally by copying versions with SHA-256 hashes and JSON metadata using only the Python standard library.

file-versioning files backup
Python
import os
import shutil
import hashlib
import json
import time
from pathlib import Path

class LocalFileVersioning:
    def __init__(self, target_dir="versioned_files", versions_dir="versions"):
        self.target_dir = Path(target_dir)
        self.versions_dir = Path(versions_dir)
        self.metadata_file = self.…
52 0 Open
Files & data medium

Create a Python Tool That Generates Professional Excel Dashboards

Generate a professional sales dashboard in an Excel workbook with styled headers, a bar chart, and formatted number cells using the openpyxl library.

openpyxl excel dashboard
Python
import openpyxl
from openpyxl.chart import BarChart, Reference
from openpyxl.styles import Font, PatternFill, Alignment, Border, Side
from openpyxl.utils import get_column_letter

def create_sales_dashboard(workbook_path: str) -> None:
    """Generate a professional sales dashboard in an Excel workbook."""
    wb = op…
47 0 Open
Files & data medium

Create a ZIP Archive of a Folder in Python

Recursively zip all files in a folder into a single archive using the standard library zipfile and pathlib modules.

zipfile pathlib archives
Python
import zipfile
from pathlib import Path

def zip_folder(source_dir: str, archive_path: str) -> None:
    """Zip all files in source_dir recursively into archive_path."""
    source = Path(source_dir)
    with zipfile.ZipFile(archive_path, "w", zipfile.ZIP_DEFLATED) as archive:
        for file_path in source.rglob("*"…
15 0 Open
Files & data medium

Download Files from Internet with Progress Bar in Python

Download a file from the internet while displaying a text progress bar in the terminal.

urllib download progress bar
Python
import urllib.request
import sys

def download_with_progress(url, filename):
    """Download a file with a simple text progress bar."""
    def report_hook(block_count, block_size, total_size):
        downloaded = block_count * block_size
        if total_size > 0:
            percent = min(100, int(downloaded * 100 …
52 0 Open
Files & data medium

Encrypt and Decrypt Files Using Python

Encrypt and decrypt files using the cryptography library's Fernet symmetric encryption.

encryption decryption fernet
Python
import os
from pathlib import Path
from cryptography.fernet import Fernet

def generate_key(key_file: Path) -> bytes:
    key = Fernet.generate_key()
    key_file.write_bytes(key)
    return key

def load_key(key_file: Path) -> bytes:
    return key_file.read_bytes()

def encrypt_file(input_path: Path, key: bytes, out…
57 0 Open
Files & data medium

Extract Hyperlinks from Word Documents in Python

Parses a .docx file using Python's standard library to extract every hyperlink's display text and target URL.

docx hyperlinks xml
Python
import zipfile
from pathlib import Path
import xml.etree.ElementTree as ET

def extract_hyperlinks_from_docx(filepath: str) -> list[dict]:
    """
    Extract all hyperlinks from a .docx file.
    Returns a list of dicts with 'text' and 'target' keys.
    """
    hyperlinks = []
    with zipfile.ZipFile(Path(filepath)…
88 0 Open
Files & data medium

Find Duplicate Web Pages by Content Similarity in Python

Compute SHA-256 hashes of file contents to detect and report duplicate HTML pages or any files in a directory.

duplicate-detection hashing sha256
Python
import hashlib
import os
from collections import defaultdict

def get_file_hash(filepath):
    """Compute SHA-256 hash of file contents."""
    sha256 = hashlib.sha256()
    with open(filepath, 'rb') as f:
        for chunk in iter(lambda: f.read(4096), b''):
            sha256.update(chunk)
    return sha256.hexdiges…
46 0 Open
Files & data medium

Generate a Beautiful Folder Tree Visualization in Python

A Python utility that creates a visual tree of a directory structure, excluding common files, with configurable depth.

folder tree directory visualization
Python
import os
from pathlib import Path

class FolderTree:
    def __init__(self, root_path=".", ignore_list=None, max_depth=3):
        self.root = Path(root_path)
        self.ignore = set(ignore_list or [".git", "__pycache__", ".DS_Store"])
        self.max_depth = max_depth
        
    def generate(self):
        tree…
67 0 Open
Files & data medium

Generate a Monthly Calendar PDF in Python

Create a Python utility that generates a monthly calendar PDF using ReportLab, with weekday headers and day numbers laid out in a grid.

calendar pdf reportlab
Python
from calendar import TextCalendar
from datetime import datetime
from reportlab.lib.pagesizes import letter
from reportlab.pdfgen import canvas
import os

def generate_monthly_calendar_pdf(year, month, filename="calendar.pdf"):
    cal = TextCalendar()
    days = cal.monthdays2calendar(year, month)
    
    month_name …
1767 0 Open
Files & data medium

How to Atomically Write Files in Python with Temp File and Rename

Write a file atomically using a temporary file and os.replace so readers never see partial writes even if the process crashes mid-write.

atomic-write tempfile fsync
Python
import os
import tempfile
from pathlib import Path

def atomic_write(path: str | Path, content: str) -> None:
    """Write content to path atomically using a temp file and rename."""
    path = Path(path)
    path.parent.mkdir(parents=True, exist_ok=True)

    fd, temp_path = tempfile.mkstemp(
        dir=str(path.par…
17 0 Open
Files & data medium

How to Audit Environment Variable Files for Missing Values in Python

A Python tool that reads an environment variable file and reports any variables with empty or missing values.

environment-variables file-audit configuration
Python
import os
import re
from pathlib import Path

def audit_env_file(filepath: str) -> None:
    """
    Audit an environment variable file for missing values.
    Prints file status and lists variables that have empty values.
    """
    path = Path(filepath)
    if not path.exists():
        print(f"Error: File '{filepa…
40 0 Open
Files & data medium

How to Automatically Extract Every Archive in a Folder with Python

Walk through a folder and extract all ZIP, RAR, and 7Z archives into separate subdirectories using Python.

zipfile rarfile py7zr
Python
import zipfile
import rarfile
import py7zr
import pathlib

def extract_archives(folder: str):
    """Extract every ZIP, RAR, and 7Z archive in the given folder."""
    folder_path = pathlib.Path(folder)
    for archive_file in folder_path.iterdir():
        suffix = archive_file.suffix.lower()
        try:
           …
38 0 Open
Files & data medium

How to Automatically Merge Hundreds of Excel Files Without Losing Formatting in Python

Merge all .xlsx files in a folder into a single Excel workbook, preserving individual sheet structures with sheet name prefixes.

excel pandas merge
Python
import pandas as pd
from pathlib import Path

def merge_excel_files(folder_path: str, output_path: str) -> None:
    """
    Merge all .xlsx files in a folder into a single Excel file,
    preserving individual sheet structures.
    """
    folder = Path(folder_path)
    excel_files = list(folder.glob("*.xlsx"))
    
…
44 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…
40 0 Open
Files & data medium

How to Compare Two Files by Content Hash Equality in Python

Compares two files by hashing their contents with SHA-256, skipping the hash if file sizes differ, and returns whether they are identical.

hashlib sha256 file-hashing
Python
import hashlib
from pathlib import Path

def file_hash(path: Path, chunk_size: int = 8192) -> str:
    sha256 = hashlib.sha256()
    with path.open("rb") as f:
        for chunk in iter(lambda: f.read(chunk_size), b""):
            sha256.update(chunk)
    return sha256.hexdigest()

def files_are_identical(file_a: Pat…
13 0 Open
Files & data medium

How to Find Duplicate Files by Size and Hash in Python

Recursively scan a directory, group files by size, then hash candidates to identify exact duplicate files.

deduplication filesystem hashlib
Python
import hashlib
from pathlib import Path

def hash_file(path, chunk_size=8192):
    hasher = hashlib.md5()
    with open(path, 'rb') as f:
        while chunk := f.read(chunk_size):
            hasher.update(chunk)
    return hasher.hexdigest()

def find_duplicates(directory):
    size_map = {}
    for path in Path(dir…
16 0 Open
Files & data medium

How to Generate Beautiful QR Codes with Embedded Logos in Python

Generate a high-error-correction QR code and paste a logo image in the center to create a branded, scannable QR code.

qrcode qrcode-generation pillow
Python
import qrcode
from PIL import Image

def generate_qr_with_logo(data, logo_path, output_path):
    qr = qrcode.QRCode(
        version=1,
        error_correction=qrcode.constants.ERROR_CORRECT_H,
        box_size=10,
        border=4,
    )
    qr.add_data(data)
    qr.make(fit=True)

    qr_img = qr.make_image(fill_c…
52 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…
48 0 Open
Files & data medium

How to Load Pickle Files Safely in Python

This code demonstrates how to load pickle files safely in Python by using a restricted unpickler that only allows specific, trusted classes, preventing arbitrary code execution from untrusted pickles.

pickle security serialization
Python
import pickle

# Default pickle.load is unsafe: it executes arbitrary code when unpickling.
class Unsafe:
    def __reduce__(self):
        return (eval, ("open('/tmp/pickle_demo.txt', 'w').write('pwned')",))

# Create a malicious payload (simulating untrusted source)
malicious_data = pickle.dumps(Unsafe())

# Safe ap…
14 0 Open

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