def mkObj[S <: Product, H, LH, V, T](fields: S)(implicit
    gen: Generic.Aux[S, H],
    lab: LabelledGeneric.Aux[T, LH],
    keys: Keys[LH],
    values: Values.Aux[T, V]
  ): T = {
    val h = gen.to(fields)
    val k = keys()
    ???
  }