def METHOD_NAME(
    self,
    url: Optional[List[str]] = None,
    depth: int = -1,
    expanded: bool = False,
    formatted: bool = True,
) -> G:
    """
    Fetch data on disk.
    Args:
        url: data path to retrieve
        depth: after url is reached, node expand tree until matches depth asked
        expanded: context parameter to determine if current node become from a expansion
        formatted: ask for raw file transformation
    Returns:
    """
    raise NotImplementedError()