code: def parse_dtype_str(cls, dtype_str):
      return {
          "torch.float16": torch.float16,
          "torch.float32": torch.float32,
          "torch.bfloat16": torch.bfloat16,
      }[dtype_str]
  
imports: import json
  import numpy
  import os
  import torch
  import types
  from megatron.global_vars import set_global_variables, set_retro_args
  from megatron.initialize import initialize_megatron, _initialize_distributed, _set_random_seed, _compile_dependencies
  from tools.retro.db.utils import get_indexed_dataset_infos, get_merged_train_dataset
  from tools.retro.main import add_retro_args
  from tools.retro.query.retro_dataset import get_retro_datasets
  from tools.retro.utils import get_args_path, get_bert_tokenizer, get_gpt_tokenizer
label_desc: Use image node_id 1 for calling the retro obj's underlying member method code with example usage: obj.parse_dtype_str(cls, dtype_str) and returns: dict