Classification extension not working with classes #1483
Description
How to reproduce
from pystac.extensions.classification import ClassificationExtension, Classification
item = pystac.Item(...)
CLASSES = [{"value": 2, "name": "cloud", "description": "Clouds", "color_hint": "B8D0EC"}, ...]
classif_ext = ClassificationExtension.ext(item.assets["asset_key"], add_if_missing=True)
classes = [Classification.create(**cls) for cls in CLASSES]
classif_ext.apply(classes=classes)
print(classif_ext.classes)What we see is None.
However we should see {'classification:classes': [{'value': 2, 'name': 'cloud', 'description': 'Clouds', 'color_hint': 'B8D0EC'}, ...]}