code: def _test_multigpu(self, test_name, test_args):
      with contextlib.redirect_stdout(StringIO()):
          with tempfile.TemporaryDirectory(test_name) as data_dir:
              log = os.path.join(data_dir, "train.log")
              create_dummy_data(data_dir)
              preprocess_translation_data(data_dir)
              train_translation_model(
                  data_dir,
                  "fconv_iwslt_de_en",
                  test_args + ["--log-file", log],
                  world_size=min(torch.cuda.device_count(), 2),
              )
              generate_main(data_dir)
              assert os.path.exists(log)
  
imports: import contextlib
  import json
  import logging
  import os
  import tempfile
  import unittest
  from io import StringIO
  import torch
  from fairseq import options
  from fairseq_cli import train
  from tests.utils import create_dummy_data, generate_main, preprocess_lm_data, preprocess_translation_data, train_language_model, train_translation_model
label_desc: Use image node_id 6 for calling the TestTranslationGPU obj's underlying member method code with example usage: obj._test_multigpu(test_name, test_args) without return types