code: def calc_max_cuda_non_model_data(self):
      if self._prev_overall_cuda != -1 and self._prev_md_cuda != -1:
          max_cuda_non_model_data = (
              self._prev_overall_cuda - self._prev_md_cuda
          )
          self._step_nmd_dict[
              self._preop_step - 1
          ] = max_cuda_non_model_data
          # compatibility of the old version.
          self._non_model_data_cuda_list.append(max_cuda_non_model_data)
  
file_path: ColossalAI/colossalai/zero/gemini/memory_tracer/memory_stats.py
imports: from typing import List, Optional
  import torch
  from .param_runtime_order import OrderedParamGenerator
label_desc: Use image node_id 2 for calling the MemStats obj's underlying member method code with example usage: obj.calc_max_cuda_non_model_data() without return types