code: def fixed(request):
      if request.param is None:
          return None
      index = dane_data.lrm.index
      gen = np.random.default_rng(0)
      return pd.DataFrame(
          gen.standard_t(10, (dane_data.lrm.shape[0], 2)),
          index=index,
          columns=["z0", "z1"],
      )
  
imports: from typing import NamedTuple
  import numpy
  from numpy.testing import assert_allclose
  import pandas
  from pandas.testing import assert_index_equal
  import pytest
  from statsmodels.datasets import danish_data
  from statsmodels.iolib.summary import Summary
  from statsmodels.tools.sm_exceptions import SpecificationWarning
  from statsmodels.tsa.ar_model import AutoReg
  from statsmodels.tsa.ardl.model import ARDL, UECM, ARDLResults, ardl_select_order
  from statsmodels.tsa.deterministic import DeterministicProcess
label_desc: Use image node_id 13 for calling a global function with example usage: fixed(request) and returns: pd, None