Change assert message.

src/callbacks.py

@@ -542,9 +542,7 @@ class IrcObjectProxy(RichReplyMethods):
     "A proxy object to allow proper nested of commands (even threaded ones)."
     def __init__(self, irc, msg, args, nested=0):
         log.verbose('IrcObjectProxy.__init__: %s' % args)
-        assert isinstance(args, list), \
-               'Args should be a list.  Don\'t call this with a string, it\s' \
-               'baaad.'
+        assert isinstance(args, list), 'Args should be a list, not a string.'
         self.irc = irc
         self.msg = msg
         self.nested = nested