# File lib/ec2/right_ec2.rb, line 436
    def describe_instances(list=[])
      link = generate_request("DescribeInstances", hash_params('InstanceId',list.to_a))
      request_cache_or_info(:describe_instances, link,  QEc2DescribeInstancesParser, @@bench, list.blank?) do |parser|
        get_desc_instances(parser.result)
      end
    rescue Exception
      on_exception
    end