code: def test_concatenate_empty_batch():
      with pytest.raises(ValueError, match="at least one"):
          batches = []
          s = TimeStepBatch.concatenate(*batches)
          del s
  
imports: import akro
  import gym.spaces
  import numpy
  import pytest
  from garage import EnvSpec, EnvStep, EpisodeBatch, StepType, TimeStep, TimeStepBatch
label_desc: Use image node_id 47 for calling a global function with example usage: test_concatenate_empty_batch() without return types