Fix _convert_NAME() so that it doesn't store locals for class bodies.

Fix list comp code generation -- emit GET_ITER instead of Const(0)
after the list.

Add CO_GENERATOR flag to generators.

Get CO_xxx flags from the new module
diff --git a/Lib/compiler/consts.py b/Lib/compiler/consts.py
index ae3d18d..c4a4868 100644
--- a/Lib/compiler/consts.py
+++ b/Lib/compiler/consts.py
@@ -1,6 +1,5 @@
-# code flags
-CO_VARARGS = 1
-CO_VARKEYWORDS = 2
+from new import * # import all the CO_xxx flags
+del classobj, code, function, instance, instancemethod, module
 
 # operation flags
 OP_ASSIGN = 'OP_ASSIGN'