Fintuning with mamba-1.4b

I would like to fintuning with mamba-1.4b instead of mamba-3b-zephyer
I just chnage the backbone_id to mamba-1.4b, but got the following error:
```
anaconda3/envs/cobra/lib/python3.9/site-packages/transformers/models/auto/auto_factory.py", line 736, in __getitem__
    model_type = self._reverse_config_mapping[key.__name__]
KeyError: 'MambaConfig'
```