In the shufledns description under Prerequisites specify "The tool also needs a list of valid solvers. The dnsvalidator project can be used to generate these lists."

You should recommend another project, this is because dnsvalidator looks like an abandoned project, no updates in the last 2 years.
In addition dnsvalidator for all those using newer versions of python3 (3.8+) will give error when running:

dnsvalidator -m -tL https://public-dns.info/nameservers.txt -threads 20 -o resolvers.txt
Traceback (most recent call last):
  File "~/dnsvalidator/dnsvalidator/dnsvalidator.py", line 15, in <module>
    from .lib.core.input import InputParser, InputHelper
ImportError: attempted relative import with no known parent package

And the solution of running the script with -m does not work.

Please consider presenting another project as an alternative to dnsvalidator.