diff --git a/docs/conf.py b/docs/conf.py
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -27,8 +27,8 @@ sys.path.insert(0, os.path.abspath('..')
 
 # Add any Sphinx extension module names here, as strings. They can be extensions
 # coming with Sphinx (named 'sphinx.ext.*') or your custom ones.
-extensions = ['sphinx.ext.autodoc', 'sphinx.ext.doctest', 
-              'sphinx.ext.intersphinx', 'sphinx.ext.todo', 
+extensions = ['sphinx.ext.autodoc', 'sphinx.ext.doctest',
+              'sphinx.ext.intersphinx', 'sphinx.ext.todo',
               'sphinx.ext.viewcode']
 
 # Add any paths that contain templates here, relative to this directory.