def __init__(self, net:Yolact, criterion:MultiBoxLoss):
        super().__init__()

        self.net = net
        self.criterion = criterion 

def set_criterion(cfg):
    return MultiBoxLoss(cfg.model.m2det_config.num_classes,
                        overlap_thresh = cfg.loss.overlap_thresh,
                        prior_for_matching = cfg.loss.prior_for_matching,
                        bkg_label = cfg.loss.bkg_label,
                        neg_mining = cfg.loss.neg_mining,
                        neg_pos = cfg.loss.neg_pos,
                        neg_overlap = cfg.loss.neg_overlap,
                        encode_target = cfg.loss.encode_target)