code: def backward(self, indexes, gy):
      x = self.get_retained_inputs()[0]
      return (gy[0] / x * (1 / math.log(10)),)
  
imports: import math
  import numpy
  from chainer import backend
  from chainer.backends import cuda
  from chainer import function_node
  from chainer import utils
  from chainer.utils import type_check
  import chainerx
label_desc: Use image node_id 4 for calling the Log10 obj's underlying member method code with example usage: obj.backward(indexes, gy) and returns: unknown