def METHOD_NAME(
    self,
    ys: torch.Tensor,
    next_tokens: torch.Tensor,
    states: List[Any],
    xs: torch.Tensor,
) -> Tuple[torch.Tensor, Any]:
    """Score new token (required).
    Args:
        ys (torch.Tensor): torch.int64 prefix tokens (n_batch, ylen).
        next_tokens (torch.Tensor): torch.int64 tokens to score (n_batch, n_token).
        states (List[Any]): Scorer states for prefix tokens.
        xs (torch.Tensor):
            The encoder feature that generates ys (n_batch, xlen, n_feat).
    Returns:
        tuple[torch.Tensor, Any]:
            Tuple of a score tensor for ys that has a shape `(n_batch, n_vocab)`
            and next states for ys
    """
    raise NotImplementedError