class_docstr: Tests that a binary file continues to work over time.
code: def test_backwards_compatibility(self):
      valid, test = testing_utils.eval_model(
          dict(
              task="integration_tests:multiturn_candidate",
              model="seq2seq",
              model_file="zoo:unittest/seq2seq/model",
              dict_file="zoo:unittest/seq2seq/model.dict",
          )
      )
  
      self.assertLessEqual(valid["ppl"], 1.01)
      self.assertGreaterEqual(valid["accuracy"], 0.999)
      self.assertGreaterEqual(valid["f1"], 0.999)
      self.assertLessEqual(test["ppl"], 1.01)
      self.assertGreaterEqual(test["accuracy"], 0.999)
      self.assertGreaterEqual(test["f1"], 0.999)
  
file_path: ParlAI/tests/test_seq2seq.py
imports: import unittest
  import parlai.utils.testing
label_desc: Use image node_id 1 for calling the TestBackwardsCompatibility obj's underlying member method code with example usage: obj.test_backwards_compatibility() without return types