Build a Bulk PDF Invoice Renamer in 55 Lines of Python

Last month, my CA messaged me at 11pm: "Bhai, send all April invoices in a single zip, named properly." I had 47 PDF invoices in my Downloads folder, all with names like Invoice (3).pdf , download.pdf , and INV_FINAL_FINAL_v2.pdf . Two hours of manual renaming wasn't on my agenda. So I wrote a Python script. By the time my chai was done, the script was done. 47 invoices renamed, audit-ready. Here's the entire thing — 55 lines, no fluff. What it does The script scans a folder of PDF invoices and