TypeError: __init__() got an unexpected keyword argument 'max_nb_epochs'

```
from pytorch_lightning import Trainer
from argparse import ArgumentParser
# from research_seed.digit_recognition.mnist import MNISTRecognizer


# def main():
model = MNISTRecognizer()
trainer = Trainer(max_nb_epochs=50,gpus=1)
trainer.fit(model)
```
pytorch-lightning==0.9.1rc1

There is error:
TypeError: __init__() got an unexpected keyword argument 'max_nb_epochs'