code: def sigmoid(x):
      return 0.5 * (np.tanh(x) + 1.0)
  
file_path: autograd/examples/generative_adversarial_net.py
imports: from __future__ import absolute_import, division
  from __future__ import print_function
  import autograd.numpy
  import autograd.numpy.random
  from autograd import grad
  from autograd.misc import flatten
  from data import load_mnist, save_images
label_desc: Use image node_id 2 for calling a global function with example usage: sigmoid(x) and returns: unknown