diff --git a/arrays_and_strings/hash_set_bst.py b/arrays_and_strings/hash_set_bst.py
index 3955a23..fe14a37 100644
--- a/arrays_and_strings/hash_set_bst.py
+++ b/arrays_and_strings/hash_set_bst.py
@@ -1,3 +1,8 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+# author: bt3gl
+
+
 class HashSet:
 
     def __init__(self):