diff --git a/jupyterhub/spawner.py b/jupyterhub/spawner.py
index cdca3c74..b31ab458 100644
--- a/jupyterhub/spawner.py
+++ b/jupyterhub/spawner.py
@@ -943,15 +943,14 @@ class Spawner(LoggingConfigurable):
         """Takes certificate paths and makes them available to the notebook server
 
         Arguments:
-            paths (dict): a list of paths for key, cert, and CA.
-            These paths will be resolvable and readable by the Hub process,
-            but not necessarily by the notebook server.
+            paths (dict): a list of paths for key, cert, and CA. These paths
+            will be resolvable and readable by the Hub process, but not
+            necessarily by the notebook server.
 
         Returns:
-            dict: a list (potentially altered) of paths for key, cert,
-            and CA.
-            These paths should be resolvable and readable
-            by the notebook server to be launched.
+            dict: a list (potentially altered) of paths for key, cert, and CA.
+            These paths should be resolvable and readable by the notebook server
+            to be launched.
 
 
         `.move_certs` is called after certs for the singleuser notebook have
@@ -1618,5 +1617,5 @@ class SimpleLocalProcessSpawner(LocalProcessSpawner):
         return env
 
     def move_certs(self, paths):
-        """No-op for installing certs"""
+        """No-op for installing certs."""
         return paths