+
+-- | This calls lookupNS, and returns the result as the second
+-- component of a tuple whose first component is the domain name
+-- itself.
+--
+-- Examples:
+--
+-- The example domain, example.com, does have NS records, but the
+-- order in which they are returned is variable, so we have to sort
+-- them to get a reliable result.
+--
+-- >>> import Data.List (sort)
+-- >>> let sort_snd (x,y) = (x, sort <$> y)
+-- >>> rs <- makeResolvSeed defaultResolvConf
+-- >>> let domain = BS.pack "example.com."
+-- >>> withResolver rs $ \resolver -> sort_snd <$> lookupNS' resolver domain
+-- ("example.com.",Just ["a.iana-servers.net.","b.iana-servers.net."])
+--