diff --git a/tools/test/topos/opticalTest.py b/tools/test/topos/opticalTest.py
index 8e316fa..2f94747 100755
--- a/tools/test/topos/opticalTest.py
+++ b/tools/test/topos/opticalTest.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python
+#!/usr/bin/python3
 
 from opticalUtils import MininetOE, LINCSwitch, LINCLink
 from mininet.topo import Topo
@@ -86,8 +86,8 @@
     if len( sys.argv ) >= 2:
         controllers = sys.argv[1:]
     else:
-        print 'Usage:sudo -E python opticalTest.py (<Controller IP>)+'
-        print 'Using localhost...\n'
+        print('Usage:sudo -E python3 opticalTest.py (<Controller IP>)+')
+        print('Using localhost...\n')
         controllers = [ '127.0.0.1' ]
 
     setLogLevel( 'info' )