Update README.md

README.md

@@ -22,7 +22,7 @@ Task: Summarization
 
 ## Usage
 ```python
-from transformers import PegasusForConditionalGeneration
+from transformers import PegasusForConditionalGeneration,BertTokenizer
 import jieba
 jieba.initialize()
 # Need to download tokenizers_pegasus.py and other Python script from Fengshenbang-LM github repo in advance,