code: def profile_dataloader(
      dataloader: Iterable[object],
      profiler: torch.profiler.profile,
      *,
      max_steps: Optional[int] = None,
      timer: Optional[TimerProtocol] = None,
      device: Optional[torch.device] = None,
  ) -> TimerProtocol:
      """
      A helper function that profiles the dataloader iterations.
  
      Args:
          dataloader: dataloader to be profiled.
          profiler: PyTorch profiler to be used. The profiler is only stepped, so it is the responsibility of the caller to start/stop the profiler.
          max_steps (optional): maximum number of steps to run for. If not set, the dataloader will run until its iterator is exhausted.
          timer (optional): timer to be used to track duration.
          device (optional): device to copy the data to. If set, this function will profile copying data to device.
      """
      timer = timer if timer is not None else Timer(cuda_sync=False)
      with timer.time("iter(dataloader)"), record_function(
          "iter(dataloader)"
      ):
          data_iter = iter(dataloader)
  
      # If max_steps is not set, run until the dataloader is exhausted
      steps_completed = 0
  
      should_move_data_to_device = device is not None
  
      while max_steps is None or (steps_completed < max_steps):
          try:
              with timer.time("next(iter)"), record_function(
                  "next(iter)"
              ):
                  data = next(data_iter)
  
              if should_move_data_to_device:
                  with timer.time(
                      "copy_data_to_device"
                  ), record_function("copy_data_to_device"):
                      # pyre-ignore [6]: device is checked as not None before calling this
                      data = copy_data_to_device(data, device)
  
              steps_completed += 1
              if profiler:
                  profiler.step()
          except StopIteration:
              break
  
      return timer
  
imports: import logging
  from typing import Iterable, Optional
  import torch
  from torch.profiler import record_function
  from torchtnt.utils.device import copy_data_to_device
  from torchtnt.utils.timer import Timer, TimerProtocol
label_desc: Use image node_id 1 for calling a global function with example usage: profile_dataloader(dataloader, profiler) and returns: timer