code: def test_past(self):
      with compat.forward_compatibility_horizon(2018, 9, 18):
          self.assertTrue(compat.forward_compatible(2020, 4, 4))
  
file_path: tensorflow/tensorflow/python/compat/compat_test.py
imports: import datetime
  import os
  from tensorflow.python.compat import compat
  from tensorflow.python.platform import test
label_desc: Use image node_id 4 for calling the CompatTest obj's underlying member method code with example usage: obj.test_past() without return types