code: def testGetNextEmpty(self):
      spec = self._data_spec()
      replay_buffer = tf_uniform_replay_buffer.TFUniformReplayBuffer(
          spec, batch_size=1, max_length=10
      )
  
      with self.assertRaisesRegexp(
          tf.errors.InvalidArgumentError,
          "TFUniformReplayBuffer is empty. Make "
          "sure to add items before sampling the buffer.",
      ):
          self.evaluate(tf.compat.v1.global_variables_initializer())
          sample, _ = replay_buffer.get_next()
          self.evaluate(sample)
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from absl.testing import parameterized
  import numpy
  import tensorflow
  from tf_agents import specs
  from tf_agents.replay_buffers import tf_uniform_replay_buffer
  from tf_agents.utils import common
  from tf_agents.utils import test_utils
label_desc: Use image node_id 6 for calling the TFUniformReplayBufferTest obj's underlying member method code with example usage: obj.testGetNextEmpty() without return types