Read mode r, write mode w, and append mode a — IITM BS previous year questions

Read mode r, write mode w, and append mode a is part of File Modes, Week 9 in Programming in Python. Prasnya files every IIT Madras BS previous year question from this subtopic here, each one with a worked explanation. Take the whole set as a timed mock and you get accuracy, pacing and per-question analysis back.