code: def test_migrate_loop_structure_after_tbptt_removal():
      """Test the loop state migration after truncated backpropagation support was removed in 2.0.0, and with it the
      training batch loop."""
      # automatic- and manual optimization state are combined into a single checkpoint to simplify testing
      state_automatic = MagicMock()
      state_manual = MagicMock()
      optim_progress_automatic = MagicMock()
      optim_progress_manual = MagicMock()
      old_batch_loop_state = MagicMock()
      old_checkpoint = {
          "loops": {
              "fit_loop": {
                  "epoch_loop.state_dict": {"any": "state"},
                  "epoch_loop.batch_loop.state_dict": old_batch_loop_state,
                  "epoch_loop.batch_loop.optimizer_loop.state_dict": state_automatic,
                  "epoch_loop.batch_loop.optimizer_loop.optim_progress": optim_progress_automatic,
                  "epoch_loop.batch_loop.manual_loop.state_dict": state_manual,
                  "epoch_loop.batch_loop.manual_loop.optim_step_progress": optim_progress_manual,
              }
          }
      }
      _set_version(
          old_checkpoint, "1.8.0"
      )  # pretend a checkpoint prior to 2.0.0
      updated_checkpoint, _ = migrate_checkpoint(
          old_checkpoint.copy(), target_version="2.0.0"
      )
      assert updated_checkpoint["loops"] == {
          "fit_loop": {
              "epoch_loop.state_dict": {
                  "any": "state",
                  "old_batch_loop_state_dict": old_batch_loop_state,
              },
              "epoch_loop.automatic_optimization.state_dict": state_automatic,
              "epoch_loop.automatic_optimization.optim_progress": optim_progress_automatic,
              "epoch_loop.manual_optimization.state_dict": state_manual,
              "epoch_loop.manual_optimization.optim_step_progress": optim_progress_manual,
          }
      }
  
imports: from unittest.mock import ANY, MagicMock
  import lightning.pytorch
  import pytest
  import torch
  from lightning.fabric.utilities.warnings import PossibleUserWarning
  from lightning.pytorch import Trainer
  from lightning.pytorch.callbacks import EarlyStopping, ModelCheckpoint
  from lightning.pytorch.demos.boring_classes import BoringModel, ManualOptimBoringModel
  from lightning.pytorch.utilities.migration import migrate_checkpoint
  from lightning.pytorch.utilities.migration.utils import _get_version, _set_legacy_version, _set_version
label_desc: Use image node_id 8 for calling a global function with example usage: test_migrate_loop_structure_after_tbptt_removal() without return types