def setUp(self):
    super(DebugIdentityV2OpTest, self).setUp()
    # Testing using a small circular-buffer size.
    self.circular_buffer_size = 4
    self.tfdbg_run_id = "test_tfdbg_run"
    self.writer = debug_events_writer.DebugEventsWriter(
        self.dump_root, self.tfdbg_run_id, self.circular_buffer_size)