conll2003 incorrect label explanation
Hi @BramVanroy,

since these fields are of type `ClassLabel` (you can check this with `dset.features`), you can inspect the possible values with:
```python
dset.features[field_name].feature.names  # .feature because it's a sequence of labels
```

and to find the mapping between names and integers, use: 
```python
dset.features[field_name].feature.int2str(value_or_values_list)  # map integer value to string value
# or
dset.features[field_name].feature.str2int(value_or_values_list)  # map string value to integer value
```


In the [conll2003](https://huggingface.co/datasets/conll2003#data-fields) README, the labels are described as follows

> - `id`: a `string` feature.
> - `tokens`: a `list` of `string` features.
> - `pos_tags`: a `list` of classification labels, with possible values including `"` (0), `''` (1), `#` (2), `$` (3), `(` (4).
> - `chunk_tags`: a `list` of classification labels, with possible values including `O` (0), `B-ADJP` (1), `I-ADJP` (2), `B-ADVP` (3), `I-ADVP` (4).
> - `ner_tags`: a `list` of classification labels, with possible values including `O` (0), `B-PER` (1), `I-PER` (2), `B-ORG` (3), `I-ORG` (4) `B-LOC` (5), `I-LOC` (6) `B-MISC` (7), `I-MISC` (8).

First of all, it would be great if we can get a list of ALL possible pos_tags.

Second, the chunk tags labels cannot be correct. The description says the values go from 0 to 4 whereas the data shows values from at least 11 to 21 and 0.

EDIT: not really a bug, sorry for mistagging.