def match(cls, responses: str | None, targets: str) -> float:
        """Exact match between targets and responses."""
        if responses is None:
            return 0
        responses = chess_transform(responses)
        targets = chess_transform(targets)

        return jaccard_index(responses, targets)
Exact match between targets and responses.
vlmeval/dataset/utils/megabench/scoring/chess_jaccard.py