code: def test_all_samples_same_location_bw(self):
      x = np.ones(100)
      kde = nparam.KDEUnivariate(x)
      with pytest.raises(
          RuntimeError, match="Selected KDE bandwidth is 0"
      ):
          kde.fit()
  
imports: import numpy
  import numpy.testing
  import pytest
  from numpy.testing import assert_allclose, assert_equal
  import statsmodels.api
label_desc: Use image node_id 3 for calling the TestKDEUnivariate obj's underlying member method code with example usage: obj.test_all_samples_same_location_bw() without return types