AttributeError: 'DatasetDict' object has no attribute 'features'
You are likely trying to get the `features` from a `DatasetDict`, a dictionary containing `Datasets`. You probably first want to index into a particular split from your `DatasetDict` i.e. `dataset['train'].features`. 

For example 

```python 
ds = load_dataset('mnist')
ds.features
```
Returns 
```python
---------------------------------------------------------------------------

AttributeError                            Traceback (most recent call last)

[<ipython-input-39-791c1f9df6c2>](https://localhost:8080/#) in <module>()
----> 1 ds.features

AttributeError: 'DatasetDict' object has no attribute 'features'
```

If we look at the dataset variable, we see it is a `DatasetDict`:

```python 
print(ds)
DatasetDict({
    train: Dataset({
        features: ['image', 'label'],
        num_rows: 60000
    })
    test: Dataset({
        features: ['image', 'label'],
        num_rows: 10000
    })
})
```

We can grab the features from a split by indexing into `train`:
```python
ds['train'].features
{'image': Image(decode=True, id=None),
 'label': ClassLabel(num_classes=10, names=['0', '1', '2', '3', '4', '5', '6', '7', '8', '9'], id=None)}
```

Hope that helps  Yes, Thanks for that clarification,
## Describe the bug
Receiving the error when trying to check for Dataset features

## Steps to reproduce the bug
from datasets import Dataset
dataset = Dataset.from_pandas(df[['id', 'words', 'bboxes', 'ner_tags', 'image_path']])

dataset.features

## Expected results
A clear and concise description of the expected results.

## Actual results
Getting the following errror

AttributeError: 'DatasetDict' object has no attribute 'features'

## Environment info
Copy-and-paste the text below in your GitHub issue.

- `datasets` version: 1.18.4
- Platform: Linux-4.14.252-131.483.amzn1.x86_64-x86_64-with-glibc2.9
- Python version: 3.6.13
- PyArrow version: 6.0.1
