Lesson 18 — Errors: try / except

Handle failures

When something goes wrong, Python raises an error and the program stops. try/except lets you catch it: risky code goes under try, and the except branch runs only if that error happens. Name the error type after except, so unexpected errors still show up.

try:
    n = int("abc")
except ValueError:
    n = 0

Why it matters: bad input and missing files are normal — a good program answers with a clear message instead of crashing.