SummarizationModule, Trainer and BertPreTrainedModel
Hi,

I wonder what's the relationship between SummarizationModule (SummarizationDistiller), Trainer and BertPreTrainedModel? I want to reimplement the distillation.py of seq2seq example and run it on the glue dataset. But I'm confused by the relationship between these three classes. 

The model parameter of Trainer is BertPreTrainedModel and the Trainer train the model. But in the SummarizationDistiller there isn't a training function. I didn't find the training process in the distillation.py and finetune.py. Should I pass SummarizationDistiller object to Trainer to train the model? Or how should I train my custom SummarizationDistiller.
Hi @ziqi-zhang,
the distillation code is written using the `pytorch-lightning` framework and `SummarizationModule` is a lightning module. You should go through the lightning docs to see how training works for lightning modules and how to customize it.

`Trainer` is transformers training helper which is different from lightning and there is no connection between the two.<|||||>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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