code: def sigmoid_deriv(y, d_y):
      """Computes derive sigmoid of y"""
      return d_y * y * (tfe.negative(y) + 1)
  
file_path: tf-encrypted/tf_encrypted/keras/activations.py
imports: import tf_encrypted
label_desc: Use image node_id 4 for calling a global function with example usage: sigmoid_deriv(y, d_y) and returns: unknown