code: def test_cached():
      item = CachedCostItem()
      assert item.cost == 2
      assert item.cost == 2
  
imports: import concurrent.futures
  import sys
  import threading
  import pytest
  from flash.core.serve._compat.cached_property import cached_property
  from flash.core.utilities.imports import _TOPIC_SERVE_AVAILABLE
label_desc: Use image node_id 1 for calling the TestCachedProperty obj's underlying member method code with example usage: obj.test_cached() without return types