@Override
    public @NotNull String toString(@NotNull SplitterProportionsDataImpl data) {
      StringBuilder result = new StringBuilder();
      String sep = "";
      for (Float proportion : data.proportions) {
        result.append(sep);
        result.append(proportion);
        sep = ",";
      }
      return result.toString();
    }
@Override
    public @NotNull String toString(@NotNull SplitterProportionsDataImpl data)