Save an API's raw reply before parsing anything from it

You call an API, parse the reply immediately, and a bug in your own parsing means calling that same API all over again.

IntermediateRead 6 minDoing: 30 minutes7 steps

▶ Start

What you'll have at the end

A script that saves the raw reply to disk, then reads it back and prints one field

Before you start

You need

Python with the requests library installed, and a real API endpoint you can already call successfully with it.

Not covered

A reply that isn't JSON, such as an image or a plain text file, needs the raw bytes saved instead of the text shown here, and retrying a failed call is a separate concern from saving what a successful one returned.

Leans on

Python Cheat SheetIts Context Managers, File Operations, and Exception Handling tables cover the with-block, the write() and read() calls, and the except-with-variable pattern this script leans on.
Python Libraries Cheat SheetIts HTTP Clients, File and Path Handling, Date and Time, and Serialization tables line requests, pathlib, datetime, and json up against their real alternatives.
REST API Cheat SheetIts HTTP Status Codes and Rate Limiting tables explain what the status code and a 429 reply actually mean once a script relies on them to decide whether to save or skip a call.
JSON Cheat SheetIts Parsing in Popular Languages table covers exactly what json.loads does with the saved text once the script reads it back.

7 steps

Where to go next

Turn a CSV export into the JSON shape an API expects

if you're calling this same API to send data shaped from a CSV rather than to read back and save what it returns, that recipe covers shaping the outgoing payload instead.

Checked 25 Aug 2026

Part of the Python cookbook