code: def test_methods(basic_data, params_only):
      y, x, _ = basic_data
      mod = RollingOLS(y, x, 150)
      res_inv = mod.fit(method="inv", params_only=params_only)
      res_lstsq = mod.fit(method="lstsq", params_only=params_only)
      res_pinv = mod.fit(method="pinv", params_only=params_only)
      assert_allclose(res_inv.params, res_lstsq.params)
      assert_allclose(res_inv.params, res_pinv.params)
  
imports: from io import BytesIO
  from itertools import product
  import warnings
  import numpy
  import pandas
  import pytest
  from numpy.testing import assert_allclose, assert_array_equal
  from statsmodels import tools
  from statsmodels.regression.linear_model import WLS
  from statsmodels.regression.rolling import RollingWLS, RollingOLS
label_desc: Use image node_id 15 for calling a global function with example usage: test_methods(basic_data, params_only) without return types