def get_metadata(self, key: str) -> Optional[dict]:
        """Retrieves the metadata for the given key.

        Args:
            key: the key to check

        Returns:
            a dict of metadata about the key
        """
        key_doc = self._store_service.get_key(self.store_name, key)
        if key_doc is None:
            return None

        return dict(
            created_at=key_doc.created_at,
            updated_at=key_doc.updated_at,
            expires_at=key_doc.expires_at,
        )
Retrieves the metadata for the given key.

        Args:
            key: the key to check

        Returns:
            a dict of metadata about the key
        
fiftyone/operators/store/store.py