Update README.md

README.md

@@ -47,6 +47,7 @@ We collect 120G novels as the pretraining data for LongLM.
    ```python\
    from transformers import T5Tokenizer, T5ForConditionalGeneration
    tokenizer = T5Tokenizer.from_pretrained('LongLM-large')
+   tokenizer.add_special_tokens({"additional_special_tokens": ["<extra_id_%d>"%d for d in range(100)]})
    model = T5ForConditionalGeneration.from_pretrained('LongLM-large')
    ```