Issue 2117.  Update compiler module to handle class decorators.
Thanks Thomas Herve
diff --git a/Tools/compiler/ast.txt b/Tools/compiler/ast.txt
index 7968a52..2dfb372 100644
--- a/Tools/compiler/ast.txt
+++ b/Tools/compiler/ast.txt
@@ -14,7 +14,7 @@
 Decorators: nodes!
 Function: decorators&, name*, argnames*, defaults!, flags*, doc*, code
 Lambda: argnames*, defaults!, flags*, code
-Class: name*, bases!, doc*, code
+Class: name*, bases!, doc*, code, decorators& = None
 Pass: 
 Break: 
 Continue: 
@@ -97,7 +97,7 @@
         self.kwargs = 1
 
 init(GenExpr):
-    self.argnames = ['[outmost-iterable]']
+    self.argnames = ['.0']
     self.varargs = self.kwargs = None
 
 init(GenExprFor):