SF patch 1631942 by Collin Winter:
(a) "except E, V" -> "except E as V"
(b) V is now limited to a simple name (local variable)
(c) V is now deleted at the end of the except block
diff --git a/Lib/csv.py b/Lib/csv.py
index 79d72b6..d911175 100644
--- a/Lib/csv.py
+++ b/Lib/csv.py
@@ -48,7 +48,7 @@
     def _validate(self):
         try:
             _Dialect(self)
-        except TypeError, e:
+        except TypeError as e:
             # We do this for compatibility with py2.3
             raise Error(str(e))