DS18B20 on Raspberry Pi

How to make a DS18B20 work with Home Assistant on a Raspberry Pi?

I know how to wire it up to GPIO pin 4.

I have MQTT installed.

I’ve seen suggestions that a thing called mqtt-io is needed and have found documentation for it at https://mqtt-io.app/2.2.9/#/

What I would like, if anyone has done this, and this is the right component to use, is exactly how to install this in the Home Assistant environment, and exactly how to configure it. As I don’t at present have a spare Raspberry Pi to try it out on I don’t want to break my live Home Assistant by getting something wrong!