code: def testFlush(self):
      win = self.WIN
      comm = self.COMM
      size = comm.Get_size()
      rank = comm.Get_rank()
      #
      for i in range(size):
          with win_lock(win, i):
              win.Flush(i)
      comm.Barrier()
      for i in range(size):
          if i == rank:
              with win_lock_all(win):
                  win.Flush_all()
          comm.Barrier()
      #
      for i in range(size):
          with win_lock(win, i):
              win.Flush_local(i)
      comm.Barrier()
      for i in range(size):
          if i == rank:
              with win_lock_all(win):
                  win.Flush_local_all()
          comm.Barrier()
  
imports: from mpi4py import MPI
  import mpiunittest
  import contextlib
  import arrayimpl
  import sys
label_desc: Use image node_id 20 for calling the BaseTestRMA obj's underlying member method code with example usage: obj.testFlush() without return types