US EPA AQI from 2.5 Air Quality Sensor Data - Helper?

I have a Davis Weatherlink AQ sensor that I’ve integrated into other home automation software I use and have written the conversion code to derive EPA AQI values 0-500 from the 2.5 particulate matter, but am moving to HA.

I’m a HA noob but it appears that if I want to display the 0-500 value, I’ll need to write a helper(?) to do that conversion because displaying the raw 2.5um data is not helpful in assessing good/bad AQI.

This has to have been written already by someone, and I’m surprised the integration that recognized the sensor does not offer this AQI range ready to use, but it is probably a different calculation outside the US. Does someone know where I can find one already made? I’m not yet up on how to do this in YAML and an example would help. Am I even thinking about how to do this correctly? Is a helper the best solution? Thanks.