def get_map_classes(cls, map_classes=None):
        """Get class names of current dataset.

        Args:
            classes (Sequence[str] | str | None): If classes is None, use
                default CLASSES defined by builtin dataset. If classes is a
                string, take it as a file name. The file contains the name of
                classes where each line contains one class name. If classes is
                a tuple or list, override the CLASSES defined by the dataset.

        Return:
            list[str]: A list of class names.
        """
        if map_classes is None:
            return cls.MAPCLASSES

        if isinstance(map_classes, str):
            # take it as a file path
            class_names = mmcv.list_from_file(map_classes)
        elif isinstance(map_classes, (tuple, list)):
            class_names = map_classes
        else:
            raise ValueError(f'Unsupported type {type(map_classes)} of map classes.')

        return class_names
Get class names of current dataset.

        Args:
            classes (Sequence[str] | str | None): If classes is None, use
                default CLASSES defined by builtin dataset. If classes is a
                string, take it as a file name. The file contains the name of
                classes where each line contains one class name. If classes is
                a tuple or list, override the CLASSES defined by the dataset.

        Return:
            list[str]: A list of class names.
        
projects/mmdet3d_plugin/datasets/nuscenes_vad_dataset.py