You can still save the state_dict to a log.txt
the output of optimizer.state_dict() is:
{'state': {}, 'param_groups': [{'lr': 0.0001, 'betas': (0.9, 0.999), 'eps': 1e-08, 'weight_decay': 0, 'amsgrad': False, 'params': [2666935098032, 2666957524496]}]}

it’s a simple json so you can save it in any format you want and load it