code: def test_lxmert_question_answering_labels_resize(self):
      config_and_inputs = self.model_tester.prepare_config_and_inputs()
      self.model_tester.resize_lxmert_num_qa_labels(*config_and_inputs)
  
imports: import copy
  import unittest
  import numpy
  from transformers import LxmertConfig, is_tf_available, is_torch_available
  from transformers.models.auto import get_values
  from transformers.testing_utils import require_torch, slow, torch_device
  from ...test_configuration_common import ConfigTester
  from ...test_modeling_common import ModelTesterMixin, ids_tensor
  from ...test_pipeline_mixin import PipelineTesterMixin
label_desc: Use image node_id 7 for calling the LxmertModelTest obj's underlying member method code with example usage: obj.test_lxmert_question_answering_labels_resize() without return types