diff --git a/dacapo/utils/affinities.py b/dacapo/utils/affinities.py
index 9e8ad3d43..9c2dcec76 100644
--- a/dacapo/utils/affinities.py
+++ b/dacapo/utils/affinities.py
@@ -9,7 +9,7 @@
 
 
 def seg_to_affgraph(seg: np.ndarray, neighborhood: List[Coordinate]) -> np.ndarray:
-    nhood : np.ndarray = np.array(neighborhood)
+    nhood: np.ndarray = np.array(neighborhood)
 
     # constructs an affinity graph from a segmentation
     # assume affinity graph is represented as: