How to use a custom Callback with Trainer.from_argparse_args

Q:

I’d like specify a custom Callback while passing argparse parameters using Trainer.from_argparse_args
How to do that?

Question copied from a github issue
https://github.com/PyTorchLightning/pytorch-lightning/issues/3648
in case someone searches for a similar question.

from_argparse_args accepts kwargs that override the args in the Namespace.
Example:

args = parser.parse_args()
trainer = Trainer.from_argparse_args(args, callbacks=[CustomCallback()])