code: def kl(self, mu, log_var):
      tmp = -0.5 * (
          log_var - tf.math.exp(log_var) - tf.math.pow(mu, 2) + 1
      )
      return tf.reshape(tmp, [-1])
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import tensorflow
  import tf_euler
  from tf_euler.python.utils.encoders import ShallowEncoder
  from tf_euler.python.mp_utils.base_gnn import BaseGNNNet
  from tf_euler.python.mp_utils.base_gae import BaseGraphAutoEncoder
label_desc: Use image node_id 2 for calling the VariationalGraphAutoEncoder obj's underlying member method code with example usage: obj.kl(mu, log_var) and returns: tf