diff --git a/python/chemiscope/structures/_shapes.py b/python/chemiscope/structures/_shapes.py
index b52346ac6..a6bb21c09 100644
--- a/python/chemiscope/structures/_shapes.py
+++ b/python/chemiscope/structures/_shapes.py
@@ -95,6 +95,7 @@ def arrow_from_vector(
     )
     return arrow
 
+
 def ellipsoid_from_tensor(tensor, scale=1.0, force_positive=False):
     """
     Returns an ellipsoid (semiaxes + quaternion) representation of
@@ -144,9 +145,10 @@ def ellipsoid_from_tensor(tensor, scale=1.0, force_positive=False):
 
     # Form the rotation matrix from eigenvectors
     rotation = eigenvectors.T
-    
+
     # converts to quaternion
     from scipy.spatial.transform import Rotation
+
     quaternion = Rotation.from_matrix(rotation).as_quat()
 
     return dict(