add docstring

objaverse_xl/abstract.py

@@ -7,7 +7,18 @@ from typing import Optional, Callable
 class ObjaverseSource(ABC):
     @abstractmethod
     def load_annotations(self, download_dir: str = "~/.objaverse") -> pd.DataFrame:
-        pass
+        """Loads the 3D object metadata as a Pandas DataFrame.
+
+        Args:
+            download_dir (str, optional): Directory to download the parquet metadata
+                file. Supports all file systems supported by fsspec. Defaults to
+                "~/.objaverse".
+
+        Returns:
+            pd.DataFrame: Metadata of the 3D objects as a Pandas DataFrame with columns
+                for the object "fileIdentifier", "license", "source", "fileType",
+                "sha256", and "metadata".
+        """
 
     @abstractmethod
     def download_objects(