class_docstr: Tests for tf2_utils methods.
code: def test_batch_concat(self):
      batch_size = 32
      inputs = [
          tf.zeros(shape=(batch_size, 2)),
          {"foo": tf.zeros(shape=(batch_size, 5, 3))},
          [tf.zeros(shape=(batch_size, 1))],
      ]
  
      output_shape = tf2_utils.batch_concat(inputs).shape.as_list()
      expected_shape = [batch_size, 2 + 5 * 3 + 1]
      self.assertSequenceEqual(output_shape, expected_shape)
  
imports: from typing import Sequence, Tuple
  from acme import specs
  from acme.tf import utils
  import numpy
  import sonnet
  import tensorflow
  from absl.testing import absltest
  from absl.testing import parameterized
label_desc: Use image node_id 1 for calling the Tf2UtilsTest obj's underlying member method code with example usage: obj.test_batch_concat() without return types