writing Datasets in a human readable format
AFAIK, there is currently no built-in method on the `Dataset` object to do this.
However, a workaround is to directly use the Arrow table backing the dataset, **but it implies loading the whole dataset in memory** (correct me if I'm mistaken @lhoestq).

You can convert the Arrow table to a pandas dataframe to save the data as csv as follows:
```python
arrow_table = dataset.data
dataframe = arrow_table.to_pandas()
dataframe.to_csv("/path/to/file.csv")
```

Similarly, you can convert the dataset to a Python dict and save it as JSON:
```python
import json
arrow_table = dataset.data
py_dict = arrow_table.to_pydict()
with open("/path/to/file.json", "w+") as f:
    json.dump(py_dict, f)
``` Indeed this works as long as you have enough memory.
It would be amazing to have export options like csv, json etc. !

It should be doable to implement something that iterates through the dataset batch by batch to write to csv for example.
There is already an `export` method but currently the only export type that is supported is `tfrecords`. Hi! `datasets` now supports `Dataset.to_csv` and `Dataset.to_json` for saving data in a human readable format.
Hi
I see there is a save_to_disk function to save data, but this is not human readable format, is there a way I could save a Dataset object in a human readable  format to a file like json? thanks @lhoestq 