diff --git a/cate/ds/esa_cci_odp.py b/cate/ds/esa_cci_odp.py
index 9c33af2d9..3fe322c2f 100644
--- a/cate/ds/esa_cci_odp.py
+++ b/cate/ds/esa_cci_odp.py
@@ -374,7 +374,7 @@ def _harmonize_info_field_names(catalogue: dict, single_field_name: str, multipl
         else:
             if catalogue[single_field_name] not in catalogue[multiple_fields_name] \
                     and (multiple_items_name is None or catalogue[single_field_name] != multiple_items_name):
-                if not instanceof(catalogue[multiple_fields_name], list):
+                if not isinstance(catalogue[multiple_fields_name], list):
                     catalogue[multiple_fields_name] = [catalogue[multiple_fields_name]]
                 catalogue[multiple_fields_name].append(catalogue[single_field_name])
             catalogue.pop(single_field_name)