code: def combine_walk(u0, u1):
      """Combines two elements of a latent-space prior sample."""
      with tf.name_scope("combine_walk"):
          return AffineUpdate(
              transition_matrix=tf.linalg.matmul(
                  u1.transition_matrix, u0.transition_matrix
              ),
              mean=tf.linalg.matvec(u1.transition_matrix, u0.mean)
              + u1.mean,
          )
  
imports: import collections
  import functools
  import numpy
  import tensorflow.compat.v2
  from tensorflow_probability.python.distributions import mvn_tril
  from tensorflow_probability.python.internal import dtype_util
  from tensorflow_probability.python.internal import prefer_static
  from tensorflow_probability.python.internal import samplers
  from tensorflow_probability.python.math import linalg
  from tensorflow_probability.python.math.scan_associative import scan_associative
label_desc: Use image node_id 2 for calling a global function with example usage: combine_walk(u0, u1) and returns: AffineUpdate