How import pickle to index?

Hello!

Tell me please how import pickle to index?

**I try:**
```

import pickle
from pynndescent import NNDescent
with open('dataset_faces.dat', 'rb') as f:
all_face_encodings = pickle.load(f)

index = NNDescent(all_face_encodings)
```
**I get error:**
`AttributeError: 'list' object has no attribute 'shape'`

Start by reproducing the reported AttributeError with the shown pickle-loading example and inspect the NNDescent entry point that receives all_face_encodings. Check the expected input type and determine whether the issue is a usage clarification or a code change; done means the example can be indexed without the reported error or the required input format is documented.

Written by the indexing model from the issue text.