diff --git a/pyiron_workflow/mixin/run.py b/pyiron_workflow/mixin/run.py
index c932b44a..b7b11c7b 100644
--- a/pyiron_workflow/mixin/run.py
+++ b/pyiron_workflow/mixin/run.py
@@ -54,7 +54,9 @@ def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
         self.running: bool = False
         self.failed: bool = False
-        self.executor: StdLibExecutor | tuple[Callable[..., StdLibExecutor], tuple, dict] | None = None
+        self.executor: (
+            StdLibExecutor | tuple[Callable[..., StdLibExecutor], tuple, dict] | None
+        ) = None
         # We call it an executor, but it can also be instructions on making one
         self.future: None | Future = None
         self._thread_pool_sleep_time: float = 1e-6