This port will be removed on 2020-12-31 if not fixed
Not sure if this project is still active, seems to have nothing going on for 6 years. But there is version 3 that supports Python 3, so maybe it can be updated.
(In reply to Steve Wills from comment #1)
updating to 3.x version may (and most probably will) break ports that depends upon it. dnspython (dns/py-dnspython) is a standard for dns stuff in python anyway. Last version that supports both python branches is in ports now.