code: def test_double_precision_pickle():
      model = BoringModel()
      plugin = DoublePrecision()
      model, _, __ = plugin.connect(model, MagicMock(), MagicMock())
      pickle.dumps(model)
  
imports: import pickle
  from unittest.mock import MagicMock
  import pytest
  import torch
  from lightning.pytorch import Trainer
  from lightning.pytorch.demos.boring_classes import BoringModel, RandomDataset
  from lightning.pytorch.plugins.precision.double import DoublePrecision
  from torch.utils.data import DataLoader, Dataset
  from tests_pytorch.helpers.runif import RunIf
label_desc: Use image node_id 3 for calling a global function with example usage: test_double_precision_pickle() without return types