Finetune T5 on other Dataset, AssertionError: assert tokenized.input_ids.shape[1] == max_length
# ❓ Questions & Help
## Details
I was trying to finetune Amazon Food Review Dataset on T5 using **Latest code from master**.

I formatted the data, as .source and .target. 

When running [finetune_t5.sh](https://github.com/huggingface/transformers/blob/master/examples/seq2seq/finetune.py),

First it gives error :  **Keyword arguments {'add_prefix_space': True} not recognized.**

And then  : `File "/content/transformers/examples/summarization/utils.py", line 51, in encode_file
    assert tokenized.input_ids.shape[1] == max_length
AssertionError`

Could you please say, whether it is a bug or I am doing something wrong?

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