code: def test_cumulative_sum_power_of_two(self):
      elems = self._maybe_static(tf.range(0, 2**4, dtype=tf.int64))
      self.assertAllEqual(
          self.evaluate(
              scan_associative(operator.add, elems, max_num_levels=8)
          ),
          self.evaluate(tf.cumsum(elems)),
      )
  
imports: import collections
  import functools
  import operator
  from absl.testing import parameterized
  import numpy
  import tensorflow.compat.v1
  import tensorflow.compat.v2
  from tensorflow_probability.python.distributions import uniform
  from tensorflow_probability.python.internal import test_util
  from tensorflow_probability.python.math import gradient
  from tensorflow_probability.python.math.scan_associative import scan_associative
label_desc: Use image node_id 3 for calling the _ScanAssociativeTest obj's underlying member method code with example usage: obj.test_cumulative_sum_power_of_two() without return types