docstr: Add a server to cluster, and run distributed function on it.
docstr_tok: ["Add","a","server","to","cluster",",","and","run","distributed","function","on","it","."]
code: def testDistributedFunctionServerAdded(self):
      """Add a server to cluster, and run distributed function on it."""
      with ops.device(self.device_t1):
          x1 = array_ops.ones([2, 2])
  
      @def_function.function
      def worker_fn(i):
          with ops.device(self.device_t2):
              mul = math_ops.matmul(i, i)
          return mul - array_ops.zeros_like(mul)
  
      # Forces function tracing and registration
      worker_fn.get_concrete_function(x1)
  
      context.update_server_def(server_def=self.server_def_s1_s2_s3)
      with ops.device(self.device_t3):
          y = worker_fn(x1)
      np.testing.assert_array_equal([[2, 2], [2, 2]], y.numpy())
  
imports: import os
  import threading
  from absl.testing import parameterized
  import numpy
  from tensorflow.core.distributed_runtime.preemption import gen_check_preemption_op
  from tensorflow.core.protobuf import cluster_pb2
  from tensorflow.core.protobuf import tensorflow_server_pb2
  from tensorflow.python import pywrap_tfe
  from tensorflow.python.eager import context
  from tensorflow.python.eager import def_function
  from tensorflow.python.eager import executor
  from tensorflow.python.framework import errors
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import math_ops
  from tensorflow.python.ops import variables
  from tensorflow.python.platform import test
  from tensorflow.python.training import coordinator
  from tensorflow.python.training import server_lib
label_desc: Use image node_id 16 for calling the DynamicClusterTest obj's underlying member method code with example usage: obj.testDistributedFunctionServerAdded() and returns: unknown