[Autotest] making /utils py3 compatible

This will allow unittests to by run in python3, thus allowing other
modules to be tested in py3 when migrating.

BUG=chromium:990593
TEST=Ran a unittest in python3 and it worked, python3 -m py_compile

Change-Id: Idd8bae0c4157cdbd6c58b2497b1938b72a62031f
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/autotest/+/2324811
Reviewed-by: Greg Edelston <gredelston@google.com>
Reviewed-by: Congbin Guo <guocb@chromium.org>
Tested-by: Derek Beckett <dbeckett@chromium.org>
Commit-Queue: Derek Beckett <dbeckett@chromium.org>
diff --git a/utils/terminal.py b/utils/terminal.py
index 94298d4..dca8197 100644
--- a/utils/terminal.py
+++ b/utils/terminal.py
@@ -1,3 +1,4 @@
+# Lint as: python2, python3
 # -*- coding: utf-8 -*-
 # Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
@@ -8,7 +9,10 @@
 This module handles terminal interaction including ANSI color codes.
 """
 
+from __future__ import absolute_import
+from __future__ import division
 from __future__ import print_function
+from six.moves import range
 
 
 class Color(object):