code: def testNoArgs(self):
      self.COMM.Barrier()
      script = None
      if self.COMM.Get_rank() == self.ROOT:
          script = childscript()
      self.COMM.Barrier()
      script = self.COMM.bcast(script, root=self.ROOT)
      child = self.COMM.Spawn(
          script,
          None,
          self.MAXPROCS,
          info=self.INFO,
          root=self.ROOT,
      )
      child.Barrier()
      child.Disconnect()
      self.COMM.Barrier()
      if self.COMM.Get_rank() == self.ROOT:
          os.remove(script)
      self.COMM.Barrier()
  
imports: from mpi4py import MPI
  import mpiunittest
  import sys, os, mpi4py
label_desc: Use image node_id 4 for calling the BaseTestSpawnSingle obj's underlying member method code with example usage: obj.testNoArgs() without return types