code: def test_check_state_bad_type(self):
      model = MC()
      # state is non-iterable
      self.assertRaises(ValueError, model._check_state, 123)
      # state is a string
      self.assertRaises(ValueError, model._check_state, "abc")
  
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 9 for calling the TestMarkovChain obj's underlying member method code with example usage: obj.test_check_state_bad_type() without return types