code: def get_step_index(cfg: LRSchedulerConf, cur_epoch: float) -> int:
      """
      Retrieves the lr step index for the given epoch.
  
      Args:
          cfg (CfgNode): Hydra / omega conf object associated with
              Learningrate scheduler. The schema can be found in
              `LRSchedulerConf` and the example configs can be found in
              `pytorchvideo_trainer/conf/module/lr_scheduler`.
          cur_epoch (float): the number of epoch of the current training stage.
      """
      steps = cfg.steps + [cfg.max_iters]
      for ind, step in enumerate(steps):  # NoQA
          if cur_epoch < step:
              break
      return ind - 1
  
file_path: pytorchvideo/pytorchvideo_trainer/pytorchvideo_trainer/module/lr_policy.py
imports: import math
  from dataclasses import dataclass
  from typing import Callable, List
  import torch
  from hydra.core.config_store import ConfigStore
  from omegaconf import MISSING
label_desc: Use image node_id 4 for calling a global function with example usage: get_step_index(cfg, cur_epoch) and returns: unknown