code: def test_set(doc):
      """std::set <-> set"""
      s = m.cast_set()
      assert s == {"key1", "key2"}
      s.add("key3")
      assert m.load_set(s)
      assert m.load_set(frozenset(s))
  
      assert doc(m.cast_set) == "cast_set() -> Set[str]"
      assert doc(m.load_set) == "load_set(arg0: Set[str]) -> bool"
  
imports: import pytest
  from pybind11_tests import ConstructorStats, UserType
  from pybind11_tests import stl
label_desc: Use image node_id 6 for calling a global function with example usage: test_set(doc) without return types