diff --git a/src/TensorFlowNET.Keras/Losses/ILossFunc.cs b/src/TensorFlowNET.Keras/Losses/ILossFunc.cs
index 45c39dd2..4795461d 100644
--- a/src/TensorFlowNET.Keras/Losses/ILossFunc.cs
+++ b/src/TensorFlowNET.Keras/Losses/ILossFunc.cs
@@ -1,8 +1,8 @@
-namespace Tensorflow.Keras.Losses
+namespace Tensorflow.Keras.Losses
 {
     public interface ILossFunc
     {
         string Reduction { get; }
-        Tensor Call(Tensor y_true, Tensor y_pred);
+        Tensor Call(Tensor y_true, Tensor y_pred, Tensor sample_weight = null);
     }
 }