code: def test_sequence_methods(self):
      tags = ["B", "I", "O", "O", "O"]
      sequence_label_field = SequenceLabelField(
          tags, self.text, label_namespace="labels"
      )
  
      assert len(sequence_label_field) == 5
      assert sequence_label_field[1] == "I"
      assert [label for label in sequence_label_field] == tags
  
imports: from collections import defaultdict
  import logging
  import pytest
  import numpy
  from allennlp.common.checks import ConfigurationError
  from allennlp.common.testing import AllenNlpTestCase
  from allennlp.data import Token, Vocabulary
  from allennlp.data.fields import TextField, SequenceLabelField
  from allennlp.data.token_indexers import SingleIdTokenIndexer
label_desc: Use image node_id 9 for calling the TestSequenceLabelField obj's underlying member method code with example usage: obj.test_sequence_methods() without return types