code: def test_timer_parse_duration(duration, expected):
      timer = Timer(duration=duration)
      assert (timer.time_remaining() == expected is None) or (
          timer.time_remaining() == expected.total_seconds()
      )
  
imports: import logging
  import time
  from datetime import timedelta
  from unittest.mock import Mock, patch
  import pytest
  from lightning.pytorch import Trainer
  from lightning.pytorch.callbacks import ModelCheckpoint
  from lightning.pytorch.callbacks.timer import Timer
  from lightning.pytorch.demos.boring_classes import BoringModel
  from lightning.pytorch.utilities.exceptions import MisconfigurationException
  from tests_pytorch.helpers.runif import RunIf
label_desc: Use image node_id 2 for calling a global function with example usage: test_timer_parse_duration(duration, expected) without return types