Cannot load ‘bookcorpusopen’
The host of this copy of the dataset (https://the-eye.eu) is down and has been down for a good amount of time ([potentially months](https://www.reddit.com/r/Roms/comments/q82s15/theeye_downdied/))

Finding this dataset is a little esoteric, as the original authors took down the official BookCorpus dataset some time ago.

There are community-created versions of BookCorpus, such as the files hosted in the link below.
https://battle.shawwn.com/sdb/bookcorpus/

And more discussion here:
https://github.com/soskek/bookcorpus

Do we want to remove this dataset entirely?  There's a fair argument for this, given that the official BookCorpus dataset was taken down by the authors.   If not, perhaps can open a PR with the link to the community-created tar above and updated dataset description. Hi! The `bookcorpusopen` dataset is not working for the same reason as explained in this comment: https://github.com/huggingface/datasets/issues/3504#issuecomment-1004564980 Hi @HUIYINXUE, it should work now that the data owners created a mirror server with all data, and we updated the URL in our library.
## Describe the bug
Cannot load 'bookcorpusopen'


## Steps to reproduce the bug
```python
dataset = load_dataset('bookcorpusopen')
```
or
```python
dataset = load_dataset('bookcorpusopen',script_version='master')
```

## Actual results
ConnectionError: Couldn't reach https://the-eye.eu/public/AI/pile_preliminary_components/books1.tar.gz

## Environment info
- `datasets` version: 1.9.0
- Platform: Linux version 3.10.0-1160.45.1.el7.x86_64
- Python version:  3.6.13
- PyArrow version: 6.0.1
