code: def _GenerateOperationPlacement(self):
      result = []
      for unused_i in range(self._num_ops):
          op_device = ()
          for unused_j in range(3):
              random_num = random.random()
              for device_index in range(self._num_devices):
                  if (
                      self._device_probabilities[device_index]
                      > random_num
                  ):
                      op_device += (device_index,)
                      break
          result.append(op_device)
      return result
  
imports: import random
  import numpy
  from google.protobuf import text_format
  from tensorflow.core.protobuf import config_pb2
  from tensorflow.python.framework import dtypes
  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 random_ops
  from tensorflow.python.ops import variables
  from tensorflow.python.platform import test
  from tensorflow.python.platform import tf_logging
label_desc: Use image node_id 3 for calling the VirtualGpuTestUtil obj's underlying member method code with example usage: obj._GenerateOperationPlacement() and returns: result