diff --git a/src/mednet/libs/segmentation/engine/adabound.py b/src/mednet/libs/segmentation/engine/adabound.py
index bf445cebd292f717e0abe4cb7ac09cd02582045e..3b37346dda2795a896612004736d4b3621601d40 100644
--- a/src/mednet/libs/segmentation/engine/adabound.py
+++ b/src/mednet/libs/segmentation/engine/adabound.py
@@ -51,13 +51,13 @@ class AdaBound(torch.optim.Optimizer):
     def __init__(
         self,
         params: list,
-        lr: float | None = 1e-3,
-        betas: tuple[float, float] | None = (0.9, 0.999),
-        final_lr: float | None = 0.1,
-        gamma: float | None = 1e-3,
-        eps: float | None = 1e-8,
-        weight_decay: float | None = 0,
-        amsbound: bool | None = False,
+        lr: float = 1e-3,
+        betas: tuple[float, float] = (0.9, 0.999),
+        final_lr: float = 0.1,
+        gamma: float = 1e-3,
+        eps: float = 1e-8,
+        weight_decay: float = 0,
+        amsbound: bool = False,
     ):
         if not 0.0 <= lr:
             raise ValueError(f"Invalid learning rate: {lr}")