- convert keys to str for None not sortable against str on py3k

diff --git a/lib/sqlalchemy/sql/schema.py b/lib/sqlalchemy/sql/schema.py
index 628d06183f190547472976af421210cc794c89e0..0626cb2b45628a80d118508cde1c3a35b6a93c41 100644 (file)
--- a/lib/sqlalchemy/sql/schema.py
+++ b/lib/sqlalchemy/sql/schema.py
@@ -3890,7 +3890,7 @@ class _SchemaTranslateMap(object):
             self.__call__ = schema_for_object
             self.hash_key = ";".join(
                 "%s=%s" % (k, map_[k])
-                for k in sorted(map_)
+                for k in sorted(map_, key=str)
             )
             self.is_default = False
         else: