diff --git a/ch06/03_bonus_imdb-classification/train-bert-hf.py b/ch06/03_bonus_imdb-classification/train-bert-hf.py
index ef3773a..aa207c9 100644
--- a/ch06/03_bonus_imdb-classification/train-bert-hf.py
+++ b/ch06/03_bonus_imdb-classification/train-bert-hf.py
@@ -236,6 +236,8 @@ if __name__ == "__main__":
 
     pad_token_id = tokenizer.encode(tokenizer.pad_token)
 
+    base_path = "."
+
     train_dataset = IMDBDataset(base_path / "train.csv", max_length=256, tokenizer=tokenizer, pad_token_id=pad_token_id)
     val_dataset = IMDBDataset(base_path / "val.csv", max_length=256, tokenizer=tokenizer, pad_token_id=pad_token_id)
     test_dataset = IMDBDataset(base_path / "test.csv", max_length=256, tokenizer=tokenizer, pad_token_id=pad_token_id)