python3: cast dict.items() to list when using +

lib/guardian/cli.py

 from .system import GuardSystemLoadError
 
+
 def add_grd_arg(parser, *args, **kwargs):
     """Add common argument to argparse parser"""
 
@@ -24,7 +25,7 @@ def add_grd_arg(parser, *args, **kwargs):
         }
 
     parser.add_argument(*args,
-                        **dict(parserargs[args].items() + kwargs.items()))
+                        **dict(list(parserargs[args].items()) + list(kwargs.items())))
 
 def init_system(args, load=False):
     """Initialize (and optionally load) system module