Python for AI Engineering· day 15 of 30
DAY 15Python

File Handling: Text, JSON & .env

Day 15 of Python for AI Engineering, completing Module 4. Make your programs remember between runs: read and write text files, save and load JSON to disk, and load configuration and secrets from .env files — the standard, safe way to keep API keys out of your code. You'll build a JSON-backed notes app that persists.

Jun 22, 2026 12 min read2.3k words

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