code: def test_threading():
      with m.ostream_redirect(stdout=True, stderr=False):
          # start some threads
          threads = []
  
          # start some threads
          for _j in range(20):
              threads.append(m.TestThread())
  
          # give the threads some time to fail
          threads[0].sleep()
  
          # stop all the threads
          for t in threads:
              t.stop()
  
          for t in threads:
              t.join()
  
          # if a thread segfaults, we don't get here
          assert True
  
imports: from contextlib import redirect_stderr, redirect_stdout
  from io import StringIO
  from pybind11_tests import iostream
label_desc: Use image node_id 22 for calling a global function with example usage: test_threading() without return types