Why is same optimizer is used for both model and classifier ?

[mayank64ce]

In main.py why is the optimizer used this way and not separate optimizers for the model and classifier ?

    parameters = list(model.parameters()) + list(classifier.parameters())
    if config.TRAIN.OPTIMIZER.NAME == 'adam':
        optimizer = optim.Adam(parameters, lr=config.TRAIN.OPTIMIZER.LR,
                               weight_decay=config.TRAIN.OPTIMIZER.WEIGHT_DECAY)
        optimizer_cc = optim.Adam(clothes_classifier.parameters(), lr=config.TRAIN.OPTIMIZER.LR,
                                  weight_decay=config.TRAIN.OPTIMIZER.WEIGHT_DECAY)