diff --git a/yapps/cli_tool.py b/yapps/cli_tool.py
index 692d3b8..0faa6e3 100755
--- a/yapps/cli_tool.py
+++ b/yapps/cli_tool.py
@@ -15,9 +15,9 @@ import os, sys, re, types
 #from six import string_types
 PY2 = sys.version_info[0] == 2
 if PY2:
-	string_types = (basestring,)
+    string_types = (basestring,)
 else:
-	string_types = (str,)
+    string_types = (str,)
 
 try: from yapps import runtime, parsetree, grammar
 except ImportError: