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/rexec.py b/Lib/rexec.py
index 37dff62..665f294 100644
--- a/Lib/rexec.py
+++ b/Lib/rexec.py
@@ -551,7 +551,7 @@
     if args and args[0] != '-':
         try:
             fp = open(args[0])
-        except IOError, msg:
+        except IOError as msg:
             print "%s: can't open file %r" % (sys.argv[0], args[0])
             return 1
     if fp.isatty():
@@ -566,7 +566,7 @@
                 r.s_apply(code.InteractiveConsole.runcode, (self, co))
         try:
             RestrictedConsole(r.modules['__main__'].__dict__).interact()
-        except SystemExit, n:
+        except SystemExit as n:
             return n
     else:
         text = fp.read()
@@ -574,7 +574,7 @@
         c = compile(text, fp.name, 'exec')
         try:
             r.s_exec(c)
-        except SystemExit, n:
+        except SystemExit as n:
             return n
         except:
             traceback.print_exc()