docstr: Called each step to evaluate the given batch size.
docstr_tok: ["Called","each","step","to","evaluate","the","given","batch","size","."]
code: def step(self, batch_size: int):
      """Called each step to evaluate the given batch size."""
      raise NotImplementedError(
          "`step` must be implemented by concrete evaluator."
      )
  
file_path: ludwig/ludwig/utils/batch_size_tuner.py
imports: import gc
  import logging
  import statistics
  import time
  from abc import ABC
  from typing import Optional
  import torch
  from ludwig.api_annotations import DeveloperAPI
  from ludwig.constants import MAX_BATCH_SIZE_DATASET_FRACTION, MIN_POSSIBLE_BATCH_SIZE
label_desc: Use image node_id 4 for calling the BatchSizeEvaluator obj's underlying member method code with example usage: obj.step(batch_size) without return types