code: def forward_gpu(self, inputs):
      (gy,) = inputs
      gx1, gx2 = cuda.elementwise(
          "S cond, T gy",
          "T gx1, T gx2",
          """
              gx1 = cond ? gy : (T)0.0;
              gx2 = cond ? (T)0.0 : gy;
              """,
          "maximum_bwd1",
      )(self.cond, gy)
      return (
          utils.sum_to(gx1, self.x1_shape),
          utils.sum_to(gx2, self.x2_shape),
      )
  
file_path: chainer/chainer/functions/math/maximum.py
imports: import numpy
  import chainer
  from chainer.backends import cuda
  from chainer import function_node
  from chainer import utils
  from chainer.utils import type_check
label_desc: Use image node_id 3 for calling the MaximumGrad obj's underlying member method code with example usage: obj.forward_gpu(inputs) and returns: utils,  utils