diff --git a/event_model/__init__.py b/event_model/__init__.py
index 6cc98f05..ff0e34ef 100644
--- a/event_model/__init__.py
+++ b/event_model/__init__.py
@@ -1808,9 +1808,7 @@ class MismatchedDataKeys(InvalidData):
 
 def _is_array(checker, instance):
     return (
-        jsonschema.validators.Draft7Validator.TYPE_CHECKER.is_type(
-            instance, "array"
-        )
+        jsonschema.validators.Draft7Validator.TYPE_CHECKER.is_type(instance, "array")
         or isinstance(instance, tuple)
         or hasattr(instance, "__array__")
     )