self.args is used for other stuff in an exception

src/filter.py

@@ -21,7 +21,7 @@ import cStringIO
 
 class MissingDestination(Exception):
     def __init__(self, args, src, dest):
-        self.args = args
+        self.parsed_args = args
         self.src = src
         self.dest = dest
         Exception.__init__(self, "destination path " + dest.path + " not found")