Reference library

Files & data

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

2 matches
Files & data easy

Create a Personal Knowledge Base That Searches Notes Instantly in Python

Build a lightweight personal knowledge base with JSON storage and instant case-insensitive full-text search across note titles and content.

json knowledge base search
Python
import json
import re
import sys

class PersonalKnowledgeBase:
    def __init__(self, file_path="kb_notes.json"):
        self.file_path = file_path
        self.notes = self._load_notes()

    def _load_notes(self):
        try:
            with open(self.file_path, "r") as f:
                return json.load(f)
    …
55 0 Open
Files & data easy

Normalize CSV Column Names to snake_case in Python

Convert CSV header names to snake_case using a regular expression and write the updated file in place.

csv regex snake-case
Python
import csv
import re
import sys


def to_snake_case(header):
    header = re.sub(r"(?<=[a-z0-9])(?=[A-Z])", "_", header)
    header = re.sub(r"[^a-zA-Z0-9]+", "_", header).strip("_").lower()
    return header


def normalize_csv_headers(input_path, output_path=None):
    with open(input_path, newline="", encoding="utf…
13 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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