Dataset Viewer issue for darragh/demo_data_raw3
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do you have an idea of why it can occur @huggingface/datasets? The dataset consists of a single parquet file. Thanks for reporting @severo.

I'm not able to reproduce that error. I get instead:
```
FileNotFoundError: [Errno 2] No such file or directory: 'orix/data/ChiSig/唐合乐-9-3.jpg'
```

Which pyarrow version are you using? Mine is 6.0.1.  OK, I get now your error when not streaming. OK!

If it's useful, the pyarrow version is 7.0.0:

https://github.com/huggingface/datasets-server/blob/487c39d87998f8d5a35972f1027d6c8e588e622d/services/worker/poetry.lock#L1537-L1543 Apparently, there is something weird with that Parquet file: its schema is:
```
images: extension<arrow.py_extension_type<pyarrow.lib.UnknownExtensionType>>
```

I have forced a right schema:
```python
from datasets import Features, Image, load_dataset

features = Features({"images": Image()})
ds = datasets.load_dataset("parquet", split="train", data_files="train-00000-of-00001.parquet", features=features)
```
and then recreated a new Parquet file:
```python
ds.to_parquet("train.parquet")
```

Now this Parquet file has the right schema:
```
images: struct<bytes: binary, path: string>
  child 0, bytes: binary
  child 1, path: string
```
and can be loaded normally:
```python
In [26]: ds = load_dataset("parquet", split="train", data_files="dataset.parquet")
n [27]: ds
Out[27]: 
Dataset({
    features: ['images'],
    num_rows: 20
})
```
### Link

https://huggingface.co/datasets/darragh/demo_data_raw3

### Description

```
Exception:     ValueError
Message:       Arrow type extension<arrow.py_extension_type<pyarrow.lib.UnknownExtensionType>> does not have a datasets dtype equivalent.
```
reported by @NielsRogge 

### Owner

No
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