flushable_loggers

# File activesupport/lib/active_support/log_subscriber.rb, line 74
      def flushable_loggers
        @@flushable_loggers ||= begin
          loggers = log_subscribers.map(&:logger)
          loggers.uniq!
          loggers.select { |l| l.respond_to?(:flush) }
        end
      end