code: def test_has_len():
      assert has_len(DataLoader(RandomDataset(1, 1)))
  
      with pytest.warns(
          UserWarning, match="`DataLoader` returned 0 length."
      ):
          assert has_len(DataLoader(RandomDataset(0, 0)))
  
      assert not has_len(DataLoader(RandomIterableDataset(1, 1)))
  
imports: import contextlib
  import os
  import random
  from unittest import mock
  from unittest.mock import Mock
  import lightning.fabric
  import numpy
  import pytest
  import torch
  from lightning.fabric.utilities.data import AttributeDict, _get_dataloader_init_args_and_kwargs, _replace_dunder_methods, _replace_value_in_saved_args, _set_sampler_epoch, _update_dataloader, _WrapAttrTag, has_iterable_dataset, has_len, suggested_max_num_workers
  from lightning.fabric.utilities.exceptions import MisconfigurationException
  from lightning_utilities.test.warning import no_warning_call
  from torch import Tensor
  from torch.utils.data import BatchSampler, DataLoader, RandomSampler
  from tests_fabric.helpers.models import RandomDataset, RandomIterableDataset
label_desc: Use image node_id 2 for calling a global function with example usage: test_has_len() without return types