Error in Bert example in Lightning demo notebook
📚 Documentation
the notebook which contains examples of MNIST, GAN, etc. has also an example how to finetune Bert which is broken. This is the error message:

`---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
 in ()
----> 1 bert_mnli_train_dataloader, bert_mnli_val_dataloader, bert_mnli_test_dataloader = generate_mnli_bert_dataloaders()
 in generate_mnli_bert_dataloaders()
11                                           pad_on_left=False,
12                                           pad_token=tokenizer.pad_token_id,
---> 13                                           pad_token_segment_id=0)
14   train_dataset = TensorDataset(torch.tensor([f.input_ids for f in features], dtype=torch.long),
15                                 torch.tensor([f.attention_mask for f in features], dtype=torch.long),
TypeError: glue_convert_examples_to_features() got an unexpected keyword argument 'pad_on_left'
`

the function generate_mnli_bert_dataloaders() calls the method glue_convert_examples_to_features() which - according to the documentation - is not handling the padding.
Fixed the error and hit the next one:

MisconfigurationException: Your val_dataloader has shuffle=True, it is best practice to turn this off for validation and test dataloaders.

I guess this is the result of using RandomSampler above.