diff --git a/blackjax/smc/partial_posteriors_path.py b/blackjax/smc/partial_posteriors_path.py
index 1279ad245..81f19716d 100644
--- a/blackjax/smc/partial_posteriors_path.py
+++ b/blackjax/smc/partial_posteriors_path.py
@@ -86,7 +86,10 @@ def log_weights_fn(x):
             key, state, num_mcmc_steps, mcmc_parameters, logposterior_fn, log_weights_fn
         )
 
-        return PartialPosteriorsSMCState(state.particles, state.weights, data_mask), info
+        return (
+            PartialPosteriorsSMCState(state.particles, state.weights, data_mask),
+            info,
+        )
 
     return step
 
diff --git a/tests/smc/test_partial_posteriors_smc.py b/tests/smc/test_partial_posteriors_smc.py
index 5d5a5e0ed..78d57a934 100644
--- a/tests/smc/test_partial_posteriors_smc.py
+++ b/tests/smc/test_partial_posteriors_smc.py
@@ -62,7 +62,12 @@ def partial_logposterior(x):
 
         data_masks = jnp.array(
             [
-                jnp.concat([jnp.ones(datapoints_chosen), jnp.zeros(dataset_size - datapoints_chosen)])
+                jnp.concat(
+                    [
+                        jnp.ones(datapoints_chosen),
+                        jnp.zeros(dataset_size - datapoints_chosen),
+                    ]
+                )
                 for datapoints_chosen in np.arange(100, 1001, 50)
             ]
         )