X fixup! X lib/zodb: zstor_2zurl: Explicitly reject MappingStorage

lib/zodb.py

@@ -373,9 +373,9 @@ def zstor_2zurl(zstor):
 
     # MappingStorage:
     if ztype == "ZODB.MappingStorage.MappingStorage":
-        raise ValueError("%s is in-RAM storage\n"  +
+        raise ValueError(("%s is in-RAM storage\n"  +
             "\tin-RAM storages are not supported:\n" +
             "\ta zurl pointing to in-RAM storage in one process would lead to\n"
-            "\tanother in-RAM storage in WCFS process." % ztype)
+            "\tanother in-RAM storage in WCFS process.") % ztype)
 
     raise NotImplementedError("don't know how to extract zurl from %r" % zstor)