code: def setUp(self):
      test_utils.setup_proxy()
      setup_imports()
      self._image_modality_config = MMFTransformerModalityConfig(
          type="image",
          key="image",
          embedding_dim=256,
          position_dim=1,
          segment_id=0,
          encoder=ImageEncoderFactory.Config(
              type=ImageEncoderTypes.identity
          ),
      )
      self._text_modality_config = MMFTransformerModalityConfig(
          type="text",
          key="text",
          embedding_dim=756,
          position_dim=128,
          segment_id=1,
          encoder=TextEncoderFactory.Config(
              type=TextEncoderTypes.identity
          ),
      )
  
imports: import gc
  import unittest
  import tests.test_utils
  import torch
  from mmf.common.sample import SampleList
  from mmf.models.mmf_transformer import MMFTransformer, MMFTransformerModalityConfig
  from mmf.models.transformers.heads.mlm import MLM
  from mmf.modules.encoders import EncoderFactory, IdentityEncoder, ImageEncoderFactory, ImageEncoderTypes, ResNet152ImageEncoder, TextEncoderFactory, TextEncoderTypes
  from mmf.utils.build import build_model
  from mmf.utils.configuration import Configuration
  from mmf.utils.env import setup_imports, teardown_imports
  from omegaconf import OmegaConf
  from tests.test_utils import skip_if_no_pytorchvideo
label_desc: Use image node_id 1 for calling the TestMMFTransformer obj's underlying member method code with example usage: obj.setUp() without return types