code: def test_list(self):
      from allennlp.common.registrable import Registrable
  
      class A(Registrable):
          pass
  
      @A.register("b")
      class B(A):
          def __init__(self, size: int) -> None:
              self.size = size
  
      class C(Registrable):
          pass
  
      @C.register("d")
      class D(C):
          def __init__(self, items: List[A]) -> None:
              self.items = items
  
      params = Params(
          {
              "type": "d",
              "items": [
                  {"type": "b", "size": 1},
                  {"type": "b", "size": 2},
              ],
          }
      )
      d = C.from_params(params)
  
      assert isinstance(d.items, list)
      assert len(d.items) == 2
      assert all(isinstance(item, B) for item in d.items)
      assert d.items[0].size == 1
      assert d.items[1].size == 2
  
imports: from typing import Dict, Iterable, List, Mapping, Optional, Set, Tuple, Union
  import pytest
  import torch
  from allennlp.common import Lazy, Params, Registrable
  from allennlp.common.from_params import FromParams, takes_arg, remove_optional, create_kwargs
  from allennlp.common.testing import AllenNlpTestCase
  from allennlp.data import DataLoader, DatasetReader, Tokenizer
  from allennlp.models import Model
  from allennlp.models.archival import load_archive
  from allennlp.common.checks import ConfigurationError
label_desc: Use image node_id 15 for calling the TestFromParams obj's underlying member method code with example usage: obj.test_list() without return types