diff --git a/binderhub/events.py b/binderhub/events.py
index 37a6ad957..d0f9289fa 100644
--- a/binderhub/events.py
+++ b/binderhub/events.py
@@ -2,9 +2,9 @@
 Emit structured, discrete events when various actions happen.
 """
 
+import datetime
 import json
 import logging
-import datetime
 
 import jsonschema
 from jupyterhub.traitlets import Callable