diff --git a/docs/conf.py b/docs/conf.py
index 458fa871e..1c772726c 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -1,5 +1,4 @@
 #!/usr/bin/env python3
-# -*- coding: utf-8 -*-
 #
 # This file is execfile()d with the current directory set to its
 # containing dir.
@@ -47,7 +46,7 @@
         },
     'examples_dirs': [os.path.join('..', 'examples')],
     'gallery_dirs': ['examples'],
-    'filename_pattern': '\.py',
+    'filename_pattern': r'\.py',
     'backreferences_dir': 'api/generated',
     'default_thumb_file': os.path.join('_static', 'siphon_150x150_white_bg.png'),
     'abort_on_example_error': True