StableCascadeUNet.from_single_file not working error runwayml/stable-diffusion-v1-5 does not appear to have a file named config.json.

i want to try this stable cascade fine tuned model https://civitai.com/models/326354/altcascade

script:
```

import torch
from math import ceil
from diffusers import (
StableCascadeDecoderPipeline,
StableCascadePriorPipeline,
StableCascadeUNet
)
# from diffusers.models import StableCascadeUNet

torch.set_grad_enabled(False)
prior_unet = StableCascadeUNet.from_single_file(
"/content/model.safetensors",
torch_dtype=torch.bfloat16
)
```

error:
```

HTTPError Traceback (most recent call last)

[/usr/local/lib/python3.10/dist-packages/huggingface_hub/utils/_errors.py](https://localhost:8080/#) in hf_raise_for_status(response, endpoint_name)
303 try:
--> 304 response.raise_for_status()
305 except HTTPError as e:

15 frames

HTTPError: 404 Client Error: Not Found for url: https://huggingface.co/runwayml/stable-diffusion-v1-5/resolve/main/config.json

The above exception was the direct cause of the following exception:

EntryNotFoundError Traceback (most recent call last)

EntryNotFoundError: 404 Client Error. (Request ID: Root=1-66679074-19a06df0021ab1f94d5e607e;ee7cdda4-5c90-4783-bea8-fae0fea95b7a)

Entry Not Found for url: https://huggingface.co/runwayml/stable-diffusion-v1-5/resolve/main/config.json.

During handling of the above exception, another exception occurred:

OSError Traceback (most recent call last)

[/usr/local/lib/python3.10/dist-packages/diffusers/configuration_utils.py](https://localhost:8080/#) in load_config(cls, pretrained_model_name_or_path, return_unused_kwargs, return_commit_hash, **kwargs)
409 )
410 except EntryNotFoundError:
--> 411 raise EnvironmentError(
412 f"{pretrained_model_name_or_path} does not appear to have a file named {cls.config_name}."
413 )

OSError: runwayml/stable-diffusion-v1-5 does not appear to have a file named config.json.
```