diff --git a/.flake8 b/.flake8
index 06d83ee9..58538de2 100644
--- a/.flake8
+++ b/.flake8
@@ -11,12 +11,11 @@
 # I100: Import statements are in the wrong order
 # I101: Imported names are in the wrong order. Should be
 ignore = E, C, W, F401, F403, F811, F841, E402, I100, I101, D400
-
+builtins = c, get_config
 exclude =
     .cache,
     .github,
     docs,
-    examples,
     jupyterhub/alembic*,
     onbuild,
     scripts,
diff --git a/examples/cull-idle/jupyterhub_config.py b/examples/cull-idle/jupyterhub_config.py
index 4668fd8a..29fdc2d6 100644
--- a/examples/cull-idle/jupyterhub_config.py
+++ b/examples/cull-idle/jupyterhub_config.py
@@ -1,4 +1,7 @@
+import sys
+
 # run cull-idle as a service
+
 c.JupyterHub.services = [
     {
         'name': 'cull-idle',
diff --git a/examples/service-announcement/announcement.py b/examples/service-announcement/announcement.py
index 2c991956..98f71da5 100644
--- a/examples/service-announcement/announcement.py
+++ b/examples/service-announcement/announcement.py
@@ -21,6 +21,7 @@ class AnnouncementRequestHandler(HubAuthenticated, web.RequestHandler):
     @web.authenticated
     def post(self):
         """Update announcement"""
+        user = self.current_user
         doc = escape.json_decode(self.request.body)
         self.storage["announcement"] = doc["announcement"]
         self.storage["timestamp"] = datetime.datetime.now().isoformat()
diff --git a/examples/service-announcement/jupyterhub_config.py b/examples/service-announcement/jupyterhub_config.py
index 31e0289c..75b23e2d 100644
--- a/examples/service-announcement/jupyterhub_config.py
+++ b/examples/service-announcement/jupyterhub_config.py
@@ -1,3 +1,4 @@
+import sys
 
 # To run the announcement service managed by the hub, add this.