new_contents: from . import ProgressiveTest
  
  from progressivis import Print
  from progressivis.io import CSVLoader
  from progressivis.stats import Sample
  from progressivis.datasets import get_dataset
  from progressivis.core import aio
  from progressivis.stats.cxxsample import Sample, CxxSample
  
  def print_repr(x):
      print(repr(x))
  
  
  class TestCxxSample(ProgressiveTest):
  #    def setUp(self):
  #        log_level(logging.INFO)
      @skipIf(CxxSample is None, "C++ module is missing")
      def test_sample(self):
          s = self.scheduler()
          csv = CSVLoader(get_dataset('bigfile'), index_col=False, header=None, scheduler=s)
          smp = Sample(samples=10,scheduler=s)
          smp.input[0] = csv.output.result
          prt = Print(proc=self.terse, scheduler=s)
          prt.input[0] = smp.output.result
          aio.run(csv.scheduler().start())
          #print(repr(smp.result))
          self.assertEqual(len(smp.result), 10)
  
  if __name__ == '__main__':
      ProgressiveTest.main()
  
subject: test for cxx_sample