code: def tearDown(self):
      del self.test_model
      del self.nuts_sampler
  
imports: import sys
  import unittest
  import numpy
  from pgmpy.factors.distributions import GaussianDistribution
  from pgmpy.sampling import HamiltonianMC, HamiltonianMCDA, GradLogPDFGaussian, NoUTurnSampler, NoUTurnSamplerDA
label_desc: Use image node_id 4 for calling the TestNUTSInference obj's underlying member method code with example usage: obj.tearDown() without return types