private void Show_final_matches(List <ConsoleLine> final_matches)
        {
            _input_output.Output_line("");
            _input_output.Output_line($"There are {Reconciliator.Num_unmatched_third_party_records()} unmatched records from {Third_party_descriptor}:");
            _input_output.Output_string_list(Reconciliator.Unmatched_third_party_records());

            _input_output.Output_line("");
            _input_output.Output_line($"There are {Reconciliator.Num_unmatched_owned_records()} unmatched records from {Owned_file_descriptor}:");
            _input_output.Output_string_list(Reconciliator.Unmatched_owned_records());

            _input_output.Output_line("");
            _input_output.Output_line($"{Reconciliator.Num_matched_third_party_records()} records have been matched:");
            _input_output.Output_all_lines(final_matches);
            _input_output.Output_line("");

            _input_output.Output_line("You can reverse one match by entering the index of the match...");
            _input_output.Output_line("...or you can reverse multiple matches, by entering a comma-separated list of indices.");
            _input_output.Output_line("Like this: '0,3,23,5,24'");
            _input_output.Output_line("");
        }