code: def exam_chunk_manager():
      world_size = torch.distributed.get_world_size()
  
      model_builder, data_gen_fn, output_transform_fn, *_ = next(
          iter(
              model_zoo.get_sub_registry("transformers_gpt_lm").values()
          )
      )
  
      sharded_ddp_model = model_builder()
      chunk_manager = init_chunk_manager(
          sharded_ddp_model,
          get_current_device(),
          hidden_dim=128,
          search_range_m=1,
          min_chunk_size_m=0,
          filter_exlarge_params=True,
          strict_ddp_flag=True,
      )
      config_dict = chunk_manager.dp_degree_chunk_size_dict
      assert len(config_dict) == 1
      assert config_dict[world_size] == 527872
  
file_path: ColossalAI/tests/test_zero/test_gemini/test_search.py
imports: import pytest
  import torch
  import colossalai
  from colossalai.testing import rerun_if_address_is_in_use, spawn
  from colossalai.utils import get_current_device
  from colossalai.zero.gemini.chunk import init_chunk_manager, search_chunk_configuration
  from tests.kit.model_zoo import model_zoo
label_desc: Use image node_id 2 for calling a global function with example usage: exam_chunk_manager() without return types