code: def tearDown(self):
      del self.variables
      del self.card
      del self.cardinalities
      del self.intel_tm
      del self.diff_tm
      del self.grade_tm
      del self.start_state
      del self.model
      del self.sample
  
imports: import sys
  import unittest
  import numpy
  from mock import call, patch
  from pandas import DataFrame
  from pgmpy.factors.discrete import State
  from pgmpy.models import MarkovChain
label_desc: Use image node_id 2 for calling the TestMarkovChain obj's underlying member method code with example usage: obj.tearDown() without return types