This one's a slightly different situation: if you have two chained calls to `map`, you can replace them with a single one. In this case:

    ... map {
      _.child(1).child(1).child.toList.filter ...
    }

Although it'd probably be better here to split it up like:

    ... map { elem =>
      val firstGrandchild = elem.child(1).child(1)
      ...
    }