📚 Documentation

Refer to: https://pytorch.org/docs/stable/generated/torch.optim.Optimizer.state_dict.html#torch.optim.Optimizer.state_dict
The Optimizer.state_dict consists of state and param_groups. param_groups is a list of dict, where each dict in the list is a param group (see here). The documentation incorrectly states that param_groups is a dict containing all parameter groups; rather, it is a list containing all parameter groups (where each parameter group is a dict).

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