code: def test_multitask_distributed(self):
      valid, test = self._distributed_train_model(
          num_epochs=50,
          task="integration_tests:overfit,integration_tests:overfit_multiturn",
          truncate=16,
      )
  
      self.assertLessEqual(valid["ppl"], 1.20)
      self.assertLessEqual(test["ppl"], 1.20)
  
      # Tests that DialogData.get() is doing the right thing
      # Ensure no duplication of examples among workers
      # It would be 200 if each worker did all the examples
      self.assertEqual(
          valid["exs"].value(),
          BATCHSIZE * inttests.EXAMPLE_SIZE + BATCHSIZE,
      )
      self.assertEqual(
          test["exs"].value(),
          BATCHSIZE * inttests.EXAMPLE_SIZE + BATCHSIZE,
      )
  
imports: import os
  import unittest
  import parlai.utils.testing
  import parlai.scripts.build_dict
  import parlai.scripts.multiprocessing_train
  import parlai.tasks.integration_tests.agents
label_desc: Use image node_id 2 for calling the TestDistributed obj's underlying member method code with example usage: obj.test_multitask_distributed() without return types