# File lib/mizuho/utils.rb, line 37
        def extract_chapter(title)
                title =~ /^((\d+\.)*) (.+)$/
                chapter = $1
                pure_title = $3
                if !chapter.nil? && !chapter.empty? && pure_title && !pure_title.empty?
                        return [chapter, pure_title]
                else
                        return nil
                end
        end