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: metadata_type.rb
    path of file: ./repos/gitlabhq/app/graphql/types/packages
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

module Types
  module Packages
    class MetadataType < BaseUnion
      graphql_name 'PackageMetadata'
      description 'Represents metadata associated with a Package'

      possible_types ::Types::Packages::Composer::MetadatumType, ::Types::Packages::Conan::MetadatumType, ::Types::Packages::Maven::MetadatumType, ::Types::Packages::Nuget::MetadatumType, 
    
      def self.resolve_type(object, context)
        case object
        when ::Packages::Composer::Metadatum
          ::Types::Packages::Composer::MetadatumType
        when ::Packages::Conan::Metadatum
          ::Types::Packages::Conan::MetadatumType
        when ::Packages::Maven::Metadatum
          ::Types::Packages::Maven::MetadatumType
        when ::Packages::Nuget::Metadatum
          ::Types::Packages::Nuget::MetadatumType
        when ::Packages::Pypi::Metadatum
          ::Types::Packages::Pypi::MetadatumType
        else
          # NOTE: This method must be kept in sync with `PackageWithoutVersionsType#metadata`,
          # which must never produce data that this discriminator cannot handle.
          raise 'Unsupported metadata type'
        end