Reference library

Files & data

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

98 matches
Files & data easy

Sync only changed files between two folders in Python

This code compares two folders and copies only the new or modified files from source to destination, skipping unchanged ones by comparing SHA-256 hashes.

files sync hashing
Python
import hashlib
from pathlib import Path
import shutil

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

def sync_files(src: s…
16 0 Open
Files & data easy

Write CSV file with csv DictWriter in Python

Write a list of dictionaries to a CSV file using Python's csv.DictWriter, including a header row.

csv file-writing dictwriter
Python
import csv
from pathlib import Path

fieldnames = ["name", "city", "age"]
rows = [
    {"name": "Alice", "city": "New York", "age": 30},
    {"name": "Bob", "city": "Los Angeles", "age": 25},
    {"name": "Charlie", "city": "Chicago", "age": 35},
]

path = Path("people.csv")
with path.open("w", newline="") as csvfile:…
16 0 Open

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Files & data — Python code examples

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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.

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