diff --git a/tests/watchlists_unittest.py b/tests/watchlists_unittest.py
index d18a86983..7af9151f9 100755
--- a/tests/watchlists_unittest.py
+++ b/tests/watchlists_unittest.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env vpython3
 # Copyright (c) 2011 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
diff --git a/watchlists.py b/watchlists.py
index f8b31c696..ee26f1029 100755
--- a/watchlists.py
+++ b/watchlists.py
@@ -121,8 +121,9 @@ class Watchlists(object):
         if name not in self._watchlists:
           continue
         if rule.search(path):
-          map(watchers.add, self._watchlists[name])
-    return list(watchers)
+          for watchlist in self._watchlists[name]:
+            watchers.add(watchlist)
+    return sorted(watchers)
 
 
 def main(argv):