diff --git a/torchrl/modules/tensordict_module/actors.py b/torchrl/modules/tensordict_module/actors.py
index b1db6c6712a..358ef2006d2 100644
--- a/torchrl/modules/tensordict_module/actors.py
+++ b/torchrl/modules/tensordict_module/actors.py
@@ -2371,7 +2371,10 @@ def forward(
                 action_entry = parent_td.get(action_key_orig[-1], None)
             if action_entry is None:
                 raise self._NO_INIT_ERR
-            if self.n_steps is not None and action_entry.shape[parent_td.ndim] != self.n_steps:
+            if (
+                self.n_steps is not None
+                and action_entry.shape[parent_td.ndim] != self.n_steps
+            ):
                 raise RuntimeError(
                     f"The action's time dimension (dim={parent_td.ndim}) doesn't match the n_steps argument ({self.n_steps}). "
                     f"The action shape was {action_entry.shape}."