my usage message:
-A,  --sA  (exist Test A)
-B,  --sB  (exist Test B)
-s <string>,  --Bs <string>  ((required)  string test)
--,  --ignore_rest  (Ignores the rest of the labeled arguments following this flag.)
--version  (Displays version information and exits.)
-h,  --help  (Displays usage information and exits.)
