Bug in Traversables exercise

[ghostbuster91]

val list = List(List(1, 2, 3), List(4, 5, 6), List(7, 8, 9))
list.transpose should be(List(
List(1,4,7), 
List(2,5,8), 
List(3,6,9)))

val list2 = List(List(1), List(4))
list2.transpose should be(List(List(1),List(4)))
Evaluation failed : Compilation Error ; ERROR -> too many arguments for method transposeFunctionTraversables: (res0: List[Int], res1: List[Int], res2: List[Int], res3: List[Int])Unit at [284, 284, 284]