diff --git a/notebooks/dreamer_v3_imagination.ipynb b/notebooks/dreamer_v3_imagination.ipynb
index 5545c47a..40ebbd74 100644
--- a/notebooks/dreamer_v3_imagination.ipynb
+++ b/notebooks/dreamer_v3_imagination.ipynb
@@ -60,7 +60,6 @@
     "import torchvision\n",
     "from lightning.fabric import Fabric\n",
     "from omegaconf import OmegaConf\n",
-    "from PIL import Image\n",
     "\n",
     "from sheeprl.algos.dreamer_v3.agent import build_agent\n",
     "from sheeprl.data.buffers import SequentialReplayBuffer\n",
diff --git a/sheeprl/algos/dreamer_v3/agent.py b/sheeprl/algos/dreamer_v3/agent.py
index 02a40a8a..2a506420 100644
--- a/sheeprl/algos/dreamer_v3/agent.py
+++ b/sheeprl/algos/dreamer_v3/agent.py
@@ -83,9 +83,7 @@ def __init__(
                 layer_args={"kernel_size": 4, "stride": 2, "padding": 1, "bias": layer_norm_cls == nn.Identity},
                 activation=activation,
                 norm_layer=[layer_norm_cls] * stages,
-                norm_args=[
-                    {**layer_norm_kw, "normalized_shape": (2**i) * channels_multiplier} for i in range(stages)
-                ],
+                norm_args=[{**layer_norm_kw, "normalized_shape": (2**i) * channels_multiplier} for i in range(stages)],
             ),
             nn.Flatten(-3, -1),
         )
diff --git a/sheeprl/data/buffers.py b/sheeprl/data/buffers.py
index 8c51c9b1..e51afadd 100644
--- a/sheeprl/data/buffers.py
+++ b/sheeprl/data/buffers.py
@@ -135,12 +135,10 @@ def to_tensor(
         return buf
 
     @typing.overload
-    def add(self, data: "ReplayBuffer", validate_args: bool = False) -> None:
-        ...
+    def add(self, data: "ReplayBuffer", validate_args: bool = False) -> None: ...
 
     @typing.overload
-    def add(self, data: Dict[str, np.ndarray], validate_args: bool = False) -> None:
-        ...
+    def add(self, data: Dict[str, np.ndarray], validate_args: bool = False) -> None: ...
 
     def add(self, data: "ReplayBuffer" | Dict[str, np.ndarray], validate_args: bool = False) -> None:
         """Add data to the replay buffer. If the replay buffer is full, then the oldest data is overwritten.
@@ -617,12 +615,10 @@ def __len__(self) -> int:
         return self.buffer_size
 
     @typing.overload
-    def add(self, data: "ReplayBuffer", validate_args: bool = False) -> None:
-        ...
+    def add(self, data: "ReplayBuffer", validate_args: bool = False) -> None: ...
 
     @typing.overload
-    def add(self, data: Dict[str, np.ndarray], validate_args: bool = False) -> None:
-        ...
+    def add(self, data: Dict[str, np.ndarray], validate_args: bool = False) -> None: ...
 
     def add(
         self,
@@ -860,8 +856,9 @@ def __len__(self) -> int:
         return self._cum_lengths[-1] if len(self._buf) > 0 else 0
 
     @typing.overload
-    def add(self, data: "ReplayBuffer", env_idxes: Sequence[int] | None = None, validate_args: bool = False) -> None:
-        ...
+    def add(
+        self, data: "ReplayBuffer", env_idxes: Sequence[int] | None = None, validate_args: bool = False
+    ) -> None: ...
 
     @typing.overload
     def add(
@@ -869,8 +866,7 @@ def add(
         data: Dict[str, np.ndarray],
         env_idxes: Sequence[int] | None = None,
         validate_args: bool = False,
-    ) -> None:
-        ...
+    ) -> None: ...
 
     def add(
         self,