def dataset_id(self) -> str:
        """The current dataset ID.

        Future requests with the client will automatically use this dataset ID.
        If the dataset ID is set, it is returned. Otherwise, the ID of the
        last modified dataset is selected.
        """
        try:
            return self._dataset_id
        except AttributeError:
            all_datasets: List[DatasetData] = self.get_datasets()
            datasets_sorted = sorted(
                all_datasets, key=lambda dataset: dataset.last_modified_at
            )
            last_modified_dataset = datasets_sorted[-1]
            self._dataset_id = last_modified_dataset.id
            warnings.warn(
                UserWarning(
                    f"Dataset has not been specified, "
                    f"taking the last modified dataset {last_modified_dataset.name} as default dataset."
                )
            )
            return self._dataset_id
The current dataset ID.

        Future requests with the client will automatically use this dataset ID.
        If the dataset ID is set, it is returned. Otherwise, the ID of the
        last modified dataset is selected.
        
lightly/api/api_workflow_client.py