diff --git a/premise/activity_maps.py b/premise/activity_maps.py
index f22a2d1d..941acc7e 100644
--- a/premise/activity_maps.py
+++ b/premise/activity_maps.py
@@ -383,7 +383,7 @@ def generate_sets_from_filters(self, filtr: dict, database=None) -> dict:
 
         # check if all keys have values
         # if not, print warning
-        #for key, val in mapping.items():
+        # for key, val in mapping.items():
         #    if not val:
         #        pass
         #        print(f"Warning: No activities found for {key} -- revise mapping.")