fix dict error in when running on python 2.6
fix dict error in when running on python 2.6

wufeifei/cobra,braveghz/cobra,braveghz/cobra,40huo/cobra,40huo/cobra,braveghz/cobra,wufeifei/cobra,40huo/cobra,40huo/cobra,braveghz/cobra,braveghz/cobra,wufeifei/cobra,wufeifei/cobra,wufeifei/cobra,40huo/cobra,40huo/cobra,braveghz/cobra,wufeifei/cobra