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

module FrozenRecord
  module Compact
    extend ActiveSupport::Concern

    module ClassMethods
      def loa
    
      def build_attributes_cache
        @_attributes_cache = @attributes.each_with_object({}) do |attr, cache|
          var = :"@#{attr}"
          cache[attr.to_s] = var
          cache[attr.to_sym] = var
        end
      end