diff --git a/daphne/server.py b/daphne/server.py
index 77c9d21..a54e3a7 100755
--- a/daphne/server.py
+++ b/daphne/server.py
@@ -285,7 +285,7 @@ class Server(object):
                             logger.error(
                                 "Exception inside application: %s",
                                 exception.__repr__(),
-                                stack_info=True
+                                stack_info=True,
                             )
                             if not disconnected:
                                 protocol.handle_exception(exception)