Method _write_pairings

tests/arenas/test_chess.py:123–125

(self, round_dir, pairings)

        return arena

    def _write_pairings(self, round_dir, pairings):
        pairings_file = round_dir / "pairings.json"
        pairings_file.write_text(json.dumps(pairings, indent=2))

    def _write_pgn(self, file_path, white: str, black: str, result: str):
        content = (