This file is just a list of DNSs to be blocked on my pi-hole.

The list is based on zoso's rolist.

If you want to use this list, you can add it in your (pi-hole's admin, under Pi-Hole's Block Lists like in the screenshot below, or manually edit your /etc/pihole/adlists.default file and add https://raw.githubusercontent.com/niladam/rolist-dns/master/rolist-dns-clean.txt to your custom list.