# File lib/heroku/commands/app.rb, line 231
      def format_bytes(amount)
        amount = amount.to_i
        return '(empty)' if amount == 0
        return amount if amount < @@kb
        return "#{(amount / @@kb).round}k" if amount < @@mb
        return "#{(amount / @@mb).round}M" if amount < @@gb
        return "#{(amount / @@gb).round}G"
      end