class_docstr: Permutate function.
class_docstr_tok: ["Permutate","function","."]
code: def backward(self, indexes, grad_outputs):
      (g,) = grad_outputs
      inds = self.indices
      (gx,) = Permutate(inds, self.axis, not self.inv).apply((g,))
      return (gx,)
  
file_path: chainer/chainer/functions/array/permutate.py
imports: import numpy
  import six
  import chainer
  from chainer import backend
  from chainer.backends import cuda
  from chainer import function_node
  from chainer.utils import type_check
label_desc: Use image node_id 5 for calling the Permutate obj's underlying member method code with example usage: obj.backward(indexes, grad_outputs) and returns: gx