code: def main(cmd=None):
      r"""Enhancemnet frontend training.
  
      Example:
  
          % python enh_train.py enh --print_config --optim adadelta \
                  > conf/train_enh.yaml
          % python enh_train.py --config conf/train_enh.yaml
      """
      EnhancementTask.main(cmd=cmd)
  
label_desc: Use image node_id 2 for calling a global function with example usage: main(cmd) without return types