code: def forward_step(self, *inputs):
      invalidInputError(
          False, "Method 'forward_step' is not implemented."
      )
  
file_path: BigDL/python/nano/src/bigdl/nano/utils/common/model.py
imports: from abc import ABC
  import yaml
  from pathlib import Path
  from bigdl.nano.utils.common import invalidInputError
label_desc: Use image node_id 3 for calling the AcceleratedModel obj's underlying member method code with example usage: obj.forward_step() without return types