TypeError: string indices must be integers

[vargas2000]

awa@awa:~/sshprank$ sudo ./sshprank.py -m '-p22 --rate=10000 -iL a.txt' -u admin -p admin -x 100 -X 100 -o global.txt
__ __
/ / ____ _________ _____ / /
/ / / __ / __ / / __ `/ __ / ///
( | ) / / / // / / / // / / / / ,<
//// // .// _,// ///||
//

  --== [ by nullsecurity.net ] ==--

[+] game started
[+] scanning and cracking targets
[/] scanning sshds
[+] game over
Traceback (most recent call last):
File "./sshprank.py", line 720, in
main(sys.argv[1:])
File "./sshprank.py", line 681, in main
crack_scan()
File "./sshprank.py", line 577, in crack_scan
targets = grep_service(future.result())
File "./sshprank.py", line 372, in grep_service
for h in scan.scan_result['scan'].keys():
TypeError: string indices must be integers