diff --git a/src/caosdb/common/models.py b/src/caosdb/common/models.py
index 00522ee614cccc79c9c56b469d00b635059260b6..0142b04477c600bade9603c1de59e850afed931e 100644
--- a/src/caosdb/common/models.py
+++ b/src/caosdb/common/models.py
@@ -2908,7 +2908,7 @@ class Container(list):
                     else:
                         try:
                             is_being_referenced.add(references.value.id)
-                        except:
+                        except AttributeError:
                             pass
 
                 if hasattr(references, 'id'):
@@ -2952,7 +2952,8 @@ class Container(list):
 
                 return self
 
-            dependencies_delete = Container()  # items which have to be deleted later because of dependencies.
+            # items which have to be deleted later because of dependencies.
+            dependencies_delete = Container()
 
             for i in range(0, int(item_count/chunk_size)+1):
                 chunk = Container()