diff --git a/doc/play/hello.go b/doc/play/hello.go
index 078ddff8f41..3badf12538b 100644
--- a/doc/play/hello.go
+++ b/doc/play/hello.go
@@ -1,3 +1,5 @@
+// You can edit this code!
+// Click here and start typing.
 package main
 
 import "fmt"