[DOC] Mistaken docs on set_format
{'login': 'NightMachinery', 'id': 36224762, 'node_id': 'MDQ6VXNlcjM2MjI0NzYy', 'avatar_url': 'https://avatars.githubusercontent.com/u/36224762?v=4', 'gravatar_id': '', 'url': 'https://api.github.com/users/NightMachinery', 'html_url': 'https://github.com/NightMachinery', 'followers_url': 'https://api.github.com/users/NightMachinery/followers', 'following_url': 'https://api.github.com/users/NightMachinery/following{/other_user}', 'gists_url': 'https://api.github.com/users/NightMachinery/gists{/gist_id}', 'starred_url': 'https://api.github.com/users/NightMachinery/starred{/owner}{/repo}', 'subscriptions_url': 'https://api.github.com/users/NightMachinery/subscriptions', 'organizations_url': 'https://api.github.com/users/NightMachinery/orgs', 'repos_url': 'https://api.github.com/users/NightMachinery/repos', 'events_url': 'https://api.github.com/users/NightMachinery/events{/privacy}', 'received_events_url': 'https://api.github.com/users/NightMachinery/received_events', 'type': 'User', 'site_admin': False}
[{'id': 1935892877, 'node_id': 'MDU6TGFiZWwxOTM1ODkyODc3', 'url': 'https://api.github.com/repos/huggingface/datasets/labels/good%20first%20issue', 'name': 'good first issue', 'color': '7057ff', 'default': True, 'description': 'Good for newcomers'}]
[]
Thanks for reporting!
### Describe the bug

https://huggingface.co/docs/datasets/v2.10.0/en/package_reference/main_classes#datasets.Dataset.set_format
<img width="700" alt="image" src="https://user-images.githubusercontent.com/36224762/221506973-ae2e3991-60a7-4d4e-99f8-965c6eb61e59.png">

While actually running it will result in:
<img width="1094" alt="image" src="https://user-images.githubusercontent.com/36224762/221507032-007dab82-8781-4319-b21a-e6e4d40d97b3.png">


### Steps to reproduce the bug

_

### Expected behavior

_

### Environment info

- `datasets` version: 2.10.0
- Platform: Linux-5.10.147+-x86_64-with-glibc2.29
- Python version: 3.8.10
- PyArrow version: 9.0.0
- Pandas version: 1.3.5
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