diff --git a/surprisal/model.py b/surprisal/model.py
index d9b7815..0175b93 100644
--- a/surprisal/model.py
+++ b/surprisal/model.py
@@ -186,7 +186,22 @@ def surprise(
         mask_mask = torch.eye(n, n)[1:, :].repeat(b, 1).bool()
         ids_with_bos_token[mask_mask] = self.tokenizer.mask_token_id
 
-        import IPython
+        # below is from ckauf and neuranna?
+        # if "within_word_l2r" == PLL_metric:
+        #     """
+        #     Future tokens belonging to the same word as the target token are masked during token inference as well.
+        #     """
+        #     mask_indices = [
+        #         [mask_pos]
+        #         + [
+        #             j
+        #             for j in range(mask_pos + 1, effective_length + 2)
+        #             if word_ids[j] == word_ids[mask_pos]
+        #         ]
+        #         if word_ids[mask_pos] is not None
+        #         else [mask_pos]
+        #         for mask_pos in range(effective_length + 2)
+        #     ]
 
         raise NotImplementedError