diff --git a/firedrake/adjoint_utils/blocks/constant.py b/firedrake/adjoint_utils/blocks/constant.py
index 7b38a063fd..d384e2dcef 100644
--- a/firedrake/adjoint_utils/blocks/constant.py
+++ b/firedrake/adjoint_utils/blocks/constant.py
@@ -1,7 +1,8 @@
-import firedrake
-import numpy
 from pyadjoint import Block, OverloadedType
+import numpy
+
 from pyadjoint.reduced_functional_numpy import gather
+import firedrake
 from .block_utils import isconstant