code: def test_padding_lengths_uses_max_instance_lengths(self):
      dataset = Batch(self.instances)
      dataset.index_instances(self.vocab)
      padding_lengths = dataset.get_padding_lengths()
      assert padding_lengths == {
          "text1": {"tokens___tokens": 5},
          "text2": {"tokens___tokens": 6},
      }
  
file_path: allennlp/tests/data/dataset_test.py
imports: import pytest
  import numpy
  from allennlp.common.checks import ConfigurationError
  from allennlp.common.testing import AllenNlpTestCase
  from allennlp.data import Instance, Token, Vocabulary
  from allennlp.data.batch import Batch
  from allennlp.data.fields import TextField, LabelField
  from allennlp.data.token_indexers import SingleIdTokenIndexer
label_desc: Use image node_id 3 for calling the TestDataset obj's underlying member method code with example usage: obj.test_padding_lengths_uses_max_instance_lengths() without return types