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: message_extractor.rb
    path of file: ./repos/stackneveroverflow/vendor/bundle/ruby/2.3.0/gems/rdoc-4.3.0/lib/rdoc/generator/pot
    
    the code of the file until where you have to start completion: ##
# Extracts message from RDoc::Store

class RDoc::Generator::POT::MessageExtractor

  ##
  # Creates a message extractor for +store+.

  def initialize store
    @store = store
    @po = RDoc::Generator::POT::PO.new
  end

  ##
  # Extracts messages from +store+, stores them into
  # RDoc::Generator::POT::PO and returns it.

  def extract
    @store.all_classes_and_modules.each do |k
    
  def extract_from_klass klass
    extract_text(klass.comment_location, klass.full_name)

    klass.each_section do |section, constants, attributes|
      extract_text(section.title ,"#{klass.full_name}: section title")
      section.comments.each do |comment|
        extract_text(comment, "#{klass.full_name}: #{section.title}")
      end
    end

    klass.each_constant do |constant|
      extract_text(constant.comment, constant.full_name)
    end

    klass.each_attribute do |attribute|
      extract_text(attribute.comment, attribute.full_name)
    end

    klass.each_method do |method|
      extract_text(method.comment, method.full_name)
    end
  end