swift ios 8 change font title of section in a tableview

I would like to change the font type and font size of a section header in a table view controller.

My code:

func tableView(tableView: UITableView, willDisplayHeaderView view: UIView, forSection section: Int) {
    let header = view as! UITableViewHeaderFooterView
    header.textLabel.textColor = UIColor.blackColor()
    header.textLabel.font = UIFont(name: "Futura", size: 38)!
}

But this doesn't work. Any ideas?

from swift ios 8 change font title of section in a tableview