code: def testExplicitDevice(self):
      with ops.Graph().as_default() as g:
          const_0 = constant_op.constant(5.0)
          with g.device("/device:GPU:0"):
              const_1 = constant_op.constant(5.0)
          with g.device("/device:GPU:1"):
              const_2 = constant_op.constant(5.0)
          with g.device("/device:CPU:0"):
              const_3 = constant_op.constant(5.0)
          with g.device("/device:CPU:1"):
              const_4 = constant_op.constant(5.0)
          with g.device("/job:ps"):
              const_5 = constant_op.constant(5.0)
  
      self.assertDeviceEqual(const_0.device, None)
      self.assertDeviceEqual(const_1.device, "/device:GPU:0")
      self.assertDeviceEqual(const_2.device, "/device:GPU:1")
      self.assertDeviceEqual(const_3.device, "/device:CPU:0")
      self.assertDeviceEqual(const_4.device, "/device:CPU:1")
      self.assertDeviceEqual(const_5.device, "/job:ps")
  
imports: from tensorflow.core.framework import attr_value_pb2
  from tensorflow.core.framework import function_pb2
  from tensorflow.core.framework import graph_pb2
  from tensorflow.core.framework import node_def_pb2
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import function
  from tensorflow.python.framework import graph_util
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import tensor_util
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops import gen_state_ops
  from tensorflow.python.ops import math_ops
  from tensorflow.python.ops import variable_v1
  from tensorflow.python.platform import test
  from tensorflow.python.util import compat
label_desc: Use image node_id 3 for calling the GraphUtilTest obj's underlying member method code with example usage: obj.testExplicitDevice() without return types