Selecting custom classes from dataset

[Manjuphoenix]

I found using "MODEL.ROI_HEADS.TRAIN_CLASSES = ['class_ids']" in config.py and setting TRAIN_CLASSES: ['class_ids'] inside the faster_rcnn_VGG.yaml might help but it does not work as expected.
Has anyone tried to filter particular classes by class_names or class_ids in the config rather than modifying the dataset itself?