Add transformers version constraint to pip install command (#6)

- Add transformers version constraint to pip install command (4e7a7cd61527588474f7f5ed80e139b73e343a9d)

README.md

@@ -72,7 +72,10 @@ Evaluation was done using the python libraries [SacreBLEU](https://github.com/mj
 Ensure you have the prerequisite python libraries installed:
 
 ```bash
-pip install transformers sentencepiece
+# The constraint imposed on the transformers version below
+# is due to the following issue:
+#    https://github.com/huggingface/transformers/issues/26271
+pip install sentencepiece "transformers>4.26.1<=4.30.2"
 ```
 
 ```python