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: tag.rb
    path of file: ./repos/dependabot-core/docker/lib/dependabot/docker
    
    the code of the file until where you have to start completion: # typed: true
# frozen_string_literal: true

require "dependabot/docker/file_parser"

module Dependabot
  module Docker
    class Tag
      WORDS_WITH_BUILD = /(?:(?:-[a-z]+)+-[0-9]+)+/
      VERSION_REGEX = /v?(?<version>[0-9]+(?:\.[0-9]+)*(?:_[0-9]+|\.[a-z0-9]+|#{WORDS_WITH_BUILD}|-(?:kb)?[0-9]+)*)/i
      VERSION_WITH_SFX = /^#{VERSION_REGEX}(?<suffix>-[a-z][a-z0-9.\-]*)?$/i
      VERSION_WITH_PFX = /^(?<prefix>[a-z][a-z0-9.\-_]*-)?#{VERSION_REGEX}$/i
      VERSION_WITH_PFX_AND_SFX = /^(?<prefix>[a-z\-_]+-)?#{VERSION_REGEX}(?
    
      def format
        return :sha_suffixed if name.match?(/(^|\-g?)[0-9a-f]{7,}$/)
        return :year_month if version.match?(/^[12]\d{3}(?:[.\-]|$)/)
        return :year_month_day if version.match?(/^[12](?:\d{5}|\d{7})(?:[.\-]|$)/)
        return :build_num if version.match?(/^\d+$/)

        # As an example, "21-ea-32", "22-ea-7", and "22-ea-jdk-nanoserver-1809"
        # are mapped to "<version>-ea-<build_num>", "<version>-ea-<build_num>",
        # and "<version>-ea-jdk-nanoserver-<build_num>" respectively.
        #
        # That means only "22-ea-7" will be considered as a viable update
        # candidate for "21-ea-32", since it's the only one that respects that
        # format.
        if version.match?(WORDS_WITH_BUILD)
          return :"<version>#{version.match(WORDS_WITH_BUILD).to_s.gsub(/-[0-9]+/, '-<build_num>')}"
        end