diff -r e51c46d12ec1 Lib/collections/__init__.py
--- a/Lib/collections/__init__.py	Sun Nov 15 18:31:34 2015 -0800
+++ b/Lib/collections/__init__.py	Wed Nov 18 15:19:15 2015 +0800
@@ -1137,7 +1137,7 @@
     def __mod__(self, args):
         return self.__class__(self.data % args)
     def __rmod__(self, format):
-        return self.__class__(format % args)
+        return self.__class__(format % self.data)
 
     # the following methods are defined in alphabetical order:
     def capitalize(self): return self.__class__(self.data.capitalize())