An outside contributor fixes a bug in someone else's project, through a
fork, a pull and a review.

## alice

You maintain a small library, `slugify`, which turns titles into URL
slugs. Create the repository and commit a README and `slugify.py` with a
function `slugify(title)` that lowercases the title and replaces spaces
with hyphens. It has a bug: punctuation such as `!` or `?` stays in the
slug. Leave the bug in. Open an issue describing it, with an example input
and the output you would expect.

## bob

You use {alice}'s `slugify` library and have hit the punctuation bug. Find
the issue about it and read the code. You cannot push to their repository,
so fix it the usual way for an outside contributor: in your own copy, on a
branch, then ask {alice} to take the change, referring to the issue. Say
on the issue that you have sent a fix.

## alice

Someone has sent a fix for the punctuation bug in `slugify`. Review it:
read what it changes. Whatever it looks like, ask for one change before
you accept it: a test file, `test_slugify.py`, covering the example from
the issue. Request the change as a review, not just a comment.

## bob

{alice} reviewed your fix to `slugify` and asked for something. Find out
what, do it on the same branch, and let them know it is ready.

## alice

Check the updated fix to `slugify`. If it now has the test, approve and
merge it, close the issue saying it was fixed, and confirm `main` has the
fix. If not, say what is missing.