#2627 Let it be known what pgen generates
diff --git a/Include/graminit.h b/Include/graminit.h
index 76da6a4..38b4dac 100644
--- a/Include/graminit.h
+++ b/Include/graminit.h
@@ -1,3 +1,5 @@
+/* Generated by Parser/pgen */
+
 #define single_input 256
 #define file_input 257
 #define eval_input 258