code: def errfn(layer, out_shape):
      """
      Random errors (deltas from a previous layer) used for bprop testing
      """
      dtypeu = np.float32
      erra = np.random.random(out_shape)
      erra = erra.astype(dtypeu)
      err = layer.be.array(erra)
      return err
  
imports: from utils import tensors_allclose, allclose_with_out
  import numpy
  import pytest
  from neon import NervanaObject
  from neon.initializers.initializer import Uniform
  from neon.layers.layer import Convolution, Deconvolution, Layer, Linear, Bias, BatchNorm
  from neon.layers.container import Sequential
label_desc: Use image node_id 5 for calling a global function with example usage: errfn(layer, out_shape) and returns: err