@classmethod
def get_latest_tasks(cls, flow_name, run_id=None, steps=None, pathspecs=None):
    """
        Return a list of (step, task, attempt, metadata_blob) for a subset of
        the tasks (consider eventual consistency) for which the latest attempt
        is done for the input `flow_name, run_id`.
        We filter the list based on `steps` if non-None.
        Alternatively, `pathspecs` can contain the exact list of pathspec(s)
        (run_id/step_name/task_id) that should be filtered.
        Note: When `pathspecs` is specified, we expect strict consistency and
        not eventual consistency in contrast to other modes.
        """
    raise NotImplementedError()
