diff --git a/planemo/workflow_lint.py b/planemo/workflow_lint.py
index 73560f263..57b5f6805 100644
--- a/planemo/workflow_lint.py
+++ b/planemo/workflow_lint.py
@@ -215,7 +215,7 @@ def check_json_for_untyped_params(j):
         lint_context.warn("Workflow does not specify a creator.")
     else:
         creators = workflow_dict.get("creator")
-        if type(creators) != list:
+        if not isinstance(creators, list):
             creators = [creators]
         for creator in creators:
             if creator.get("class", "").lower() == "person" and "identifier" in creator: