'Find the metadata for a particular course asset.
Args:
asset_key (AssetKey): locator containing original asset filename
Returns:
asset metadata (AssetMetadata) -or- None if not found'

@strip_key
@contract(asset_key='AssetKey')
def find_asset_metadata(self, asset_key, **kwargs):

    store = self._get_modulestore_for_courselike(asset_key.course_key)
    return store.find_asset_metadata(asset_key, **kwargs)
