code: def test_pack_unpack(seeded_rng):
      shapes = [[2, 3], [3], [3, 4, 2], [1, 5]]
      mats = [
          tf.random.stateless_normal(shape=shape, seed=[0, 0])
          for shape in shapes
      ]
      flatmats = pack_trainable_vars(mats)
      unflatmats = unpack_trainable_vars(flatmats, mats)
      for mat_in, mat_out in zip(mats, unflatmats):
          assert tf.math.reduce_all(tf.equal(mat_in, mat_out))
  
imports: from brainiak.matnormal.utils import pack_trainable_vars, unpack_trainable_vars, flatten_cholesky_unique, unflatten_cholesky_unique
  import tensorflow
  import numpy
  import numpy.testing
label_desc: Use image node_id 1 for calling a global function with example usage: test_pack_unpack(seeded_rng) without return types