Fix assertion errors in debug build, brought on by PEP 308 patch.
diff --git a/Python/ast.c b/Python/ast.c
index 94c877d..3f2a9f3 100644
--- a/Python/ast.c
+++ b/Python/ast.c
@@ -537,7 +537,7 @@
         return NULL;
 
     for (i = 0; i < NCH(n); i += 2) {
-        REQ(CHILD(n, i), test);
+        assert(TYPE(CHILD(n, i)) == test || TYPE(CHILD(n, i)) == old_test);
 
         expression = ast_for_expr(c, CHILD(n, i));
         if (!expression)