How to display posts by expiration date

I would like to know how to list posts by expiration date in ascending order.

I am developing a site with a Genesis child theme. I found a piece of code that apparently works, but I have not been able to get it too. I posted this code in my functions file. Do I need to add customer fields or customer post class?

• https://gist.github.com/anonymous/242ec351bfa50ad511e2

has anyone tried to do this with this plugin?

thank you!

https://www.ads-software.com/plugins/post-expirator/