code: def test_exceptions(data):
      if isinstance(data, pd.DataFrame):
          y, x = data.y, data.x
      else:
          y, x = data[:, :2].T
      with pytest.raises(
          ValueError, match="Unknown trend. Must be one of"
      ):
          engle_granger(y, x, trend="nc")
  
file_path: arch/arch/tests/unitroot/test_engle_granger.py
imports: import numpy
  from numpy.testing import assert_allclose
  import pandas
  import pytest
  from statsmodels.iolib.summary import Summary
  from arch.unitroot._engle_granger import engle_granger_cv, engle_granger_pval
  from arch.unitroot._shared import ResidualCointegrationTestResult, _cross_section
  from arch.unitroot.cointegration import engle_granger
label_desc: Use image node_id 8 for calling a global function with example usage: test_exceptions(data) without return types