Reference library

Files & data

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

3 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…
50 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

Browse by section

Each section groups closely related Python snippets.

Files & data — Python code examples

What you will find here

This page collects files & data snippets — short, copy-ready Python you can paste into our free online IDE and run without installing anything. Each sample includes a plain-English explanation and the full source code.

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.