diff --git a/tests/test_assembly.py b/tests/test_assembly.py
index ca51c0c7..c3d3a15a 100644
--- a/tests/test_assembly.py
+++ b/tests/test_assembly.py
@@ -221,4 +221,6 @@ def test_empty_solve(nested_assy):
 
 def test_expression_grammar(nested_assy):
 
-    nested_assy.constrain("TOP@faces@>Z", "SECOND/BOTTOM@vertices@>X and >Y and >Z", "Plane")
+    nested_assy.constrain(
+        "TOP@faces@>Z", "SECOND/BOTTOM@vertices@>X and >Y and >Z", "Plane"
+    )