code: def test_reduce_add(self, xp, dtype):
      x = testing.shaped_random((3, 4, 5), xp=xp, dtype=dtype, seed=0)
      indices = testing.shaped_random(
          (20,), xp=xp, dtype=numpy.int32, scale=4, seed=1
      )
      return xp.add.reduceat(x, indices, axis=1)
  
imports: import numpy
  import pytest
  import cupy
  from cupy import testing
label_desc: Use image node_id 1 for calling the TestUfuncReduceAt obj's underlying member method code with example usage: obj.test_reduce_add(xp, dtype) and returns: xp