diff --git a/docs/conf.py b/docs/conf.py
index 3486fb3..9b73a5b 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -1,4 +1,18 @@
 # -*- coding: utf-8 -*-
+
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+# implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
 #
 # Cryptography documentation build configuration file, created by
 # sphinx-quickstart on Tue Aug  6 19:19:14 2013.
@@ -11,6 +25,8 @@
 # All configuration values have a default; values that are commented out
 # serve to show the default.
 
+from __future__ import absolute_import, division, print_function
+
 import os
 import sys