code: def get_sum_func(self):
      raise NotImplementedError()
  
imports: import unittest
  import numpy
  import pytest
  import cupy
  import cupy._core._accelerator
  from cupy import _core
  from cupy import testing
label_desc: Use image node_id 1 for calling the AbstractReductionTestBase obj's underlying member method code with example usage: obj.get_sum_func() without return types