class ChangeSet:
    def __init__(self) -> None:
        self.operations : list[dict[str, str]] = []

    def add(self, type: str, id: str) -> None:
        self.operations.append({ 'operation': 'add', 'type': type, 'id': id })

    def delete(self, type: str, id: str) -> None:
        self.operations.append({ 'operation': 'delete', 'type': type, 'id': id })

    def update(self, type: str, id: str, property: str) -> None:
        self.operations.append({ 'operation': 'update', 'type': type, 'id': id, 'property': property })