code: def testBcast(self):
      size = self.COMM.Get_size()
      rank = self.COMM.Get_rank()
      for array, typecode in arrayimpl.loop():
          for root in range(size):
              check = arrayimpl.scalar(root)
              if rank == root:
                  buf = array(root, typecode, root)
              else:
                  buf = array(-1, typecode, root)
              StartWaitFree(
                  self.COMM.Bcast_init(buf.as_mpi(), root=root)
              )
              for value in buf:
                  self.assertEqual(value, check)
  
imports: from mpi4py import MPI
  import mpiunittest
  import arrayimpl
  from functools import reduce
label_desc: Use image node_id 2 for calling the BaseTestCCOBuf obj's underlying member method code with example usage: obj.testBcast() without return types