code: def test_random_sanity_check(self):
      rng = test_util.test_np_rng()
      x = rng.rand(100)
      cov_reducer = covariance_reducer.CovarianceReducer()
      final_cov = self.evaluate(test_fixtures.reduce(cov_reducer, x))
      self.assertNear(np.var(x, ddof=0), final_cov, err=1e-6)
  
file_path: probability/tensorflow_probability/python/experimental/mcmc/covariance_reducer_test.py
imports: import collections
  import numpy
  import tensorflow.compat.v2
  from tensorflow_probability.python.distributions import normal
  from tensorflow_probability.python.experimental.mcmc import covariance_reducer
  from tensorflow_probability.python.experimental.mcmc.internal import test_fixtures
  from tensorflow_probability.python.internal import test_util
label_desc: Use image node_id 1 for calling the CovarianceReducersTest obj's underlying member method code with example usage: obj.test_random_sanity_check() without return types