code: def test_prob_from_sample(self, sample):
      model = MC(["a", "b"], [2, 2])
      sample.return_value = self.sample
      probabilities = model.prob_from_sample(
          [State("a", 1), State("b", 0)]
      )
      self.assertEqual(list(probabilities), [1] * 50 + [0] * 50)
  
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 26 for calling the TestMarkovChain obj's underlying member method code with example usage: obj.test_prob_from_sample(sample) without return types