DAdaptation effect and values?

[G-force78]

Ive noticed this new optimization method, it is suggested this is this suitable argument to use,
decouple=True weight_decay=0.6
What do the different values do? Is there an optimal range of decay?
Many thanks

EDIT:
Actually getting an error including weight_decay 0.6

train_network.py: error: unrecognized arguments: weight_decay=0.6
Traceback (most recent call last):
  File "/usr/local/bin/accelerate", line 8, in <module>
    sys.exit(main())
  File "/usr/local/lib/python3.8/dist-packages/accelerate/commands/accelerate_cli.py", line 45, in main
    args.func(args)
  File "/usr/local/lib/python3.8/dist-packages/accelerate/commands/launch.py", line 1104, in launch_command
    simple_launcher(args)
  File "/usr/local/lib/python3.8/dist-packages/accelerate/commands/launch.py", line 567, in simple_launcher
    raise subprocess.CalledProcessError(returncode=process.returncode, cmd=cmd)

[G-force78]

and another error..

prepare optimizer, data loader etc.
Traceback (most recent call last):
  File "train_network.py", line 507, in <module>
    train(args)
  File "train_network.py", line 150, in train
    optimizer_name, optimizer_args, optimizer = train_util.get_optimizer(args, trainable_params)
  File "/content/kohya-trainer/library/train_util.py", line 1551, in get_optimizer
    key, value = arg.split('=')
ValueError: too many values to unpack (expected 2)
Traceback (most recent call last):
  File "/usr/local/bin/accelerate", line 8, in <module>
    sys.exit(main())
  File "/usr/local/lib/python3.8/dist-packages/accelerate/commands/accelerate_cli.py", line 45, in main
    args.func(args)
  File "/usr/local/lib/python3.8/dist-packages/accelerate/commands/launch.py", line 1104, in launch_command
    simple_launcher(args)
  File "/usr/local/lib/python3.8/dist-packages/accelerate/commands/launch.py", line 567, in simple_launcher
    raise subprocess.CalledProcessError(returncode=process.returncode, cmd=cmd)