question: private void verifyUniqueKeys ( List < KV < Integer , Query > > queries ) { Set < Integer > keys = new HashSet < > ( ) ; for ( KV < Integer , Query > kv : queries ) { keys . add ( kv . getKey ( ) ) ; } assertEquals ( keys . size ( ) , queries . size ( ) ) ; }
target:  A helper function that verifies if all the queries have unique keys. 