code: def test_fast_final_eval(self):
      valid, test = testing_utils.train_model(
          {
              "task": "integration_tests",
              "validation_max_exs": 10,
              "model": "repeat_label",
              "short_final_eval": True,
              "num_epochs": 1.0,
          }
      )
      self.assertEqual(valid["exs"], 10, "Validation exs is wrong")
      self.assertEqual(test["exs"], 10, "Test exs is wrong")
  
imports: import os
  import unittest
  import json
  import parlai.utils.logging
  import parlai.utils.testing
  from parlai.utils.io import PathManager
  from parlai.core.metrics import AverageMetric
  from parlai.core.worlds import create_task
  from parlai.core.opt import Opt
  from parlai.core.params import ParlaiParser
  from parlai.core.agents import register_agent, Agent
  from parlai.scripts.eval_model import get_task_world_logs
label_desc: Use image node_id 2 for calling the TestTrainModel obj's underlying member method code with example usage: obj.test_fast_final_eval() without return types