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_attributes.rb
    path of file: ./repos/shrine/lib/shrine/plugins
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

class Shrine
  module Plugins
    # Documentation can be found on https://shrinerb.com/docs/plugins/metadata_attributes
    module MetadataAttributes
      def self.load_dependencies(uploader, *)
        uploader.plugin :entity
      end

      def self.configure(up
    
        def metadata_attributes
          values = {}

          self.class.metadata_attributes.each do |source, destination|
            metadata_attribute = destination.is_a?(Symbol) ? :"#{name}_#{destination}" : :"#{destination}"

            next unless record.respond_to?(metadata_attribute)

            values[metadata_attribute] = file && file.metadata[source.to_s]
          end

          values
        end