class_docstr: Sum axes to output an array of a given shape.
code: def backward(self, indexes, grad_outputs):
      (gy,) = grad_outputs
      (x_node,) = self.inputs
      return (chainer.functions.broadcast_to(gy, x_node.shape),)
  
imports: import numpy
  import six
  import chainer
  from chainer import backend
  from chainer import function_node
  from chainer import utils
  from chainer.utils import type_check
  import chainerx
label_desc: Use image node_id 3 for calling the SumTo obj's underlying member method code with example usage: obj.backward(indexes, grad_outputs) and returns: chainer