code: def test_trace_save_and_restore(self):
      t = MyTrackable()
      save_fn, restore_fn = tracing_utils.trace_save_and_restore(t)
      self.assertDictEqual({"a": 0, "b": 1}, self.evaluate(save_fn()))
      restore_fn(
          {"a": constant_op.constant(2), "b": constant_op.constant(3)}
      )
      self.assertDictEqual({"a": 2, "b": 3}, self.evaluate(save_fn()))
  
file_path: tensorflow/tensorflow/python/saved_model/tracing_utils_test.py
imports: from tensorflow.python.eager import def_function
  from tensorflow.python.eager import test
  from tensorflow.python.framework import constant_op
  from tensorflow.python.ops import control_flow_ops
  from tensorflow.python.ops import variables
  from tensorflow.python.saved_model import tracing_utils
  from tensorflow.python.trackable import base
label_desc: Use image node_id 1 for calling the TracingUtilsTest obj's underlying member method code with example usage: obj.test_trace_save_and_restore() without return types