expensive how expensive well it's actually not a too hard calculation to to compute this assume you use some publicly available labeling tool such as Amazon Sage make a ground truth for example they charge you I think if I remember correct around four US dollars per labeled image then as we said before you can do 30 images per hour because you can do you need two minutes per image and then of course it's not going to be you labeling but probably you're going to employ some working student for example it does the labeling and that