diff --git a/utils/utils.py b/utils/utils.py
index 929f6ba4..82b75d41 100755
--- a/utils/utils.py
+++ b/utils/utils.py
@@ -349,7 +349,8 @@ class FocalLoss(nn.Module):
 
     def forward(self, pred, true):
         loss = self.loss_fcn(pred, true)
-        # loss *= self.alpha * (1.000001 - torch.exp(-loss)) ** self.gamma  # non-zero power for gradient stability
+        # p_t = torch.exp(-loss)
+        # loss *= self.alpha * (1.000001 - p_t) ** self.gamma  # non-zero power for gradient stability
 
         # TF implementation https://github.com/tensorflow/addons/blob/v0.7.1/tensorflow_addons/losses/focal_loss.py
         pred_prob = torch.sigmoid(pred)  # prob from logits