code: def testSideEffect(self):
      counter_var = variables.Variable(0)
  
      def dataset_fn():
          return dataset_ops.Dataset.range(10)
  
      def reduce_fn(state, value):
          counter_var.assign_add(1)
          return state + value
  
      @def_function.function
      def fn():
          _ = dataset_fn().reduce(np.int64(0), reduce_fn)
          return "hello"
  
      self.evaluate(counter_var.initializer)
      self.assertEqual(self.evaluate(fn()), b"hello")
      self.assertEqual(self.evaluate(counter_var), 10)
  
imports: import time
  from absl.testing import parameterized
  import numpy
  from tensorflow.python.data.experimental.ops import testing
  from tensorflow.python.data.kernel_tests import test_base
  from tensorflow.python.data.ops import dataset_ops
  from tensorflow.python.eager import def_function
  from tensorflow.python.framework import combinations
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import errors
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import sparse_tensor
  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
label_desc: Use image node_id 8 for calling the ReduceTest obj's underlying member method code with example usage: obj.testSideEffect() and returns: dataset_ops, unknown, str