class_docstr: Main class for model parallel with data parallel training.
docstr: Save all training state in a checkpoint file.
code: def save_checkpoint(self, filename, extra_state):
      """Save all training state in a checkpoint file."""
      extra_state[
          "rng_tracker_states"
      ] = get_cuda_rng_tracker().get_states()
      super().save_checkpoint(filename, extra_state)
  
file_path: fairseq/fairseq/model_parallel/megatron_trainer.py
imports: from fairseq.dataclass.configs import FairseqConfig
  from fairseq.distributed import utils
  from fairseq.trainer import Trainer
label_desc: Use image node_id 3 for calling the MegatronTrainer obj's underlying member method code with example usage: obj.save_checkpoint(filename, extra_state) without return types