diff --git a/pyhdx/plot.py b/pyhdx/plot.py
index b0c41152..25338a85 100644
--- a/pyhdx/plot.py
+++ b/pyhdx/plot.py
@@ -1141,7 +1141,7 @@ def get(self, item, default=None):
         except KeyError:
             return default
 
-
+# should be a frozen dataclas
 CMAP_NORM_DEFAULTS = ColorTransforms()