code: def test_error():
      y, x, _ = gen_data(250, 2, True)
      with pytest.raises(
          ValueError, match="reset must be a positive integer"
      ):
          RollingWLS(
              y,
              x,
          ).fit(reset=-1)
      with pytest.raises(ValueError):
          RollingWLS(y, x).fit(method="unknown")
      with pytest.raises(ValueError, match="min_nobs must be larger"):
          RollingWLS(y, x, min_nobs=1)
      with pytest.raises(ValueError, match="min_nobs must be larger"):
          RollingWLS(y, x, window=60, min_nobs=100)
  
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 11 for calling a global function with example usage: test_error() without return types