datasets doesn't support NSP? should I implement my custom DataCollator or function for dataset.map?
As the title, I haven't find NSP dataset, there is only transformers.TextDatasetForNextSentencePrediction, but it's not work while loading data by `load_dataset(...)`.

So have I to implement my custom DataCollator or function for dataset.map? Which one is better?

Or I miss something?  
Pinging @sgugger <|||||>Yes, you have to implement your own function for preprocessing the data.<|||||>This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

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