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/plat-mac/EasyDialogs.py b/Lib/plat-mac/EasyDialogs.py
index 1bd46a8..340e3ed 100644
--- a/Lib/plat-mac/EasyDialogs.py
+++ b/Lib/plat-mac/EasyDialogs.py
@@ -651,7 +651,7 @@
     try:
         rr = Nav.NavChooseFile(args)
         good = 1
-    except Nav.error, arg:
+    except Nav.error as arg:
         if arg[0] != -128: # userCancelledErr
             raise Nav.error, arg
         return None
@@ -704,7 +704,7 @@
     try:
         rr = Nav.NavPutFile(args)
         good = 1
-    except Nav.error, arg:
+    except Nav.error as arg:
         if arg[0] != -128: # userCancelledErr
             raise Nav.error, arg
         return None
@@ -764,7 +764,7 @@
     try:
         rr = Nav.NavChooseFolder(args)
         good = 1
-    except Nav.error, arg:
+    except Nav.error as arg:
         if arg[0] != -128: # userCancelledErr
             raise Nav.error, arg
         return None