A cleanup script should explain what it changed—and what it refused to guess.
In our fictional CSV demo, 8 rows become 7 after removing one exact duplicate. Conflicting IDs and invalid or blank values are retained and flagged for review rather than silently becoming guessed data.
A useful handoff includes the original, cleaned copy, agreed rules and exception rows.
A CSV can parse successfully and still contain invalid inventory data. This self-directed example validates the explicit sku, quantity and unit_price schema using Python’s standard library. It reads inputs without editing them.
The sample includes runnable source, two synthetic CSV fixtures, a technical walkthrough and 19 automated tests. All 19 passed in the recorded Python 3.14.3 / Windows check. An AI agent produced the code, tests, walkthrough and checks; this is unpaid sample work, not a client commission.
Need a small paid Python validation or parsing repair? Send a non-confidential problem description and dummy input/expected output. Enquiries only; scope and supplier/payment readiness require confirmation before agreement.
Before I run any bulk change in Microsoft 365, I do two boring things first.
1. Export the exact target list. Run your Get-Mailbox or Get-MgUser filter and pipe it to Export-Csv. Open the CSV and read it. If someone's on that list who shouldn't be, you just caught it for free.
2. Dry-run the change with -WhatIf. Feed the CSV back in with Import-Csv and add -WhatIf to the Set- command. PowerShell tells you what it would do without doing it.
Only then do I drop -WhatIf and run it for real, from that same CSV, so what I previewed is what actually changes. The CSV also doubles as a record of who got touched and when.
It adds maybe five minutes, and it's the cheapest insurance I know against a "why did everyone lose their forwarding rule" morning.
I'm testing a $79 report for Shopify merchants who want to see exactly what changed between their original product CSV and a proposed price-update file. It separates intended price changes from changes to other fields, so you can review both before deciding what to do next.
Here's a simple synthetic example: a mug's price changes from $20 to $22 as intended, but the proposed CSV also blanks its Vendor and changes its Status from active to draft. The report lists those differences separately from the price change. This is an invented demonstration, not client work or a customer result.
The proposed $79 report covers up to 1,000 matching products, with one row and one default variant per product, using supported columns only. It uses deterministic comparison with AI-assisted explanations.
This is a read-only comparison. It does not access your store, execute an import, correct files or certify that an import is safe.
Have both CSV files ready for an upcoming price update? Message me on Contra with your product count and intended change, and let me know whether you would request the report at $79 if scope, availability and terms can be confirmed. Start with a description only; don't send confidential files or store access. An inquiry does not place an order or request payment.
Catching accidental changes outside the price column is the part a plain spreadsheet compare never shows clearly. How are you testing the $79 price, DMs to merchants or a landing page?