code: def test_fit_zero_variance(self, implementation):
      # Example from issue #2 on GitHub.
      # this data has singular covariance matrix
      X = np.asarray(
          [
              [
                  7.15000000e02,
                  5.8500000e02,
                  0.00000000e00,
                  0.00000000e00,
              ],
              [
                  7.15000000e02,
                  5.2000000e02,
                  1.04705811e00,
                  -6.03696289e01,
              ],
              [
                  7.15000000e02,
                  4.5500000e02,
                  7.20886230e-01,
                  -5.27055664e01,
              ],
              [
                  7.15000000e02,
                  3.9000000e02,
                  -4.57946777e-01,
                  -7.80605469e01,
              ],
              [
                  7.15000000e02,
                  3.2500000e02,
                  -6.43127441e00,
                  -5.59954834e01,
              ],
              [
                  7.15000000e02,
                  2.6000000e02,
                  -2.90063477e00,
                  -7.80220947e01,
              ],
              [
                  7.15000000e02,
                  1.9500000e02,
                  8.45532227e00,
                  -7.03294373e01,
              ],
              [
                  7.15000000e02,
                  1.3000000e02,
                  4.09387207e00,
                  -5.83621216e01,
              ],
              [
                  7.15000000e02,
                  6.5000000e01,
                  -1.21667480e00,
                  -4.48131409e01,
              ],
          ]
      )
  
      h = self.new_hmm(implementation)
      h.fit(X)
  
imports: import numpy
  from numpy.testing import assert_allclose, assert_array_less
  import pytest
  from sklearn.utils import check_random_state
  from ..hmm import GMMHMM
  from .test_gmm_hmm import create_random_gmm
  from .None import assert_log_likelihood_increasing, normalized
label_desc: Use image node_id 9 for calling the GMMHMMTestMixin obj's underlying member method code with example usage: obj.test_fit_zero_variance(implementation) without return types