You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: base_tube.rb
    path of file: ./repos/sequencescape/lib/label_printer/label_printer/label
    
    the code of the file until where you have to start completion: # frozen_string_literal: true
module LabelPrinter
  module Label
    class BaseTube
      include Label::MultipleLabels

      def build_label(tube)
        {
          first_line: first_line(tube),
          second_line: second_line(tube),
          third_line: third_line(tube),
          round_label_top_line: round_label_top_line(tube),
          round_label_bottom_line: round_label_bottom_line(tube),
          barcode: barcode(tube),
          label_n
    
      def first_line(tube); end

      def second_line(tube)
        tube.barcode_number
      end

      def third_line(_tube)
        date_today
      end

      def round_label_top_line(tube)
        tube.prefix
      end

      def round_label_bottom_line(tube)
        tube.barcode_number
      end

      def barcode(tube)
        tube.machine_barcode
      end

      def tubes
        @tubes || []
      end

      def assets
        tubes
      end

      def date_today
        Date.today.strftime('%e-%^b-%Y')
      end
    end