code: def test_lstm_aggregation():
      x = torch.randn(6, 16)
      index = torch.tensor([0, 0, 1, 1, 1, 2])
  
      aggr = LSTMAggregation(16, 32)
      assert str(aggr) == "LSTMAggregation(16, 32)"
  
      with pytest.raises(ValueError, match="is not sorted"):
          aggr(x, torch.tensor([0, 1, 0, 1, 2, 1]))
  
      out = aggr(x, index)
      assert out.size() == (3, 32)
  
label_desc: Use image node_id 1 for calling a global function with example usage: test_lstm_aggregation() without return types