diff --git a/lib/iris/__init__.py b/lib/iris/__init__.py
index 64d1fe64c9..96095bb74a 100644
--- a/lib/iris/__init__.py
+++ b/lib/iris/__init__.py
@@ -143,6 +143,7 @@ def callback(cube, field, filename):
 #: To be used when copying a cube to make the new cube dataless.
 DATALESS = "NONE"
 
+
 class Future(threading.local):
     """Run-time configuration controller."""