code: def setup_class(cls):
      cls.data = load()
  
imports: from statsmodels.compat.pandas import assert_series_equal
  from io import StringIO
  import warnings
  import numpy
  import numpy.testing
  import pandas
  import patsy
  import pytest
  from statsmodels.datasets import cpunish
  from statsmodels.datasets.longley import load, load_pandas
  from statsmodels.formula.api import ols
  from statsmodels.formula.formulatools import make_hypotheses_matrices
  from statsmodels.tools import add_constant
  from statsmodels.tools.testing import assert_equal
label_desc: Use image node_id 1 for calling the CheckFormulaOLS obj's underlying member method code with example usage: obj.setup_class(cls) without return types