AttributeError: 'LambdaLR' object has no attribute 'get_last_lr'
I am trying to run the summarization example using BART and getting the following error.

```
tqdm_dict = {"loss": "{:.3f}".format(avg_loss), "lr": self.lr_scheduler.get_last_lr()[-1]}
AttributeError: 'LambdaLR' object has no attribute 'get_last_lr'
```

The error occurred at this [line](https://github.com/huggingface/transformers/blob/master/examples/transformer_base.py#L101). I am using PyTorch 1.3.

I encountered the same problem, have you solved it？<|||||>Upgrading to PyTorch 1.4 would solve that issue :)

Current `master` branch recommends that:

https://github.com/huggingface/transformers/blob/4e817ff41885063e08bb3bcd63e5adfd835b9911/setup.py#L70<|||||>Thank you so much, I have solved it.<|||||>`get_last_lr` is introduced in pytorch 1.4.0 . Maybe you need to upgrade your pytorch.<|||||>If you really are stuck with PyTorch <= 1.3 please feel free to open a PR to fix this with backward compatibility<|||||>I upgraded pytorch to v1.5.0, but run_glue.py with Bert model failed. So, you may have to set it to 1.4.0 