code: def test_state_count(self):
      e = ParameterEstimator(self.m1, self.d1)
      self.assertEqual(e.state_counts("A").values.tolist(), [[2], [1]])
      self.assertEqual(
          e.state_counts("C").values.tolist(),
          [[0.0, 0.0, 1.0, 0.0], [1.0, 1.0, 0.0, 0.0]],
      )
  
file_path: pgmpy/pgmpy/tests/test_estimators/test_ParameterEstimator.py
imports: import unittest
  from numpy import NaN
  from pandas import DataFrame
  from pgmpy.estimators import ParameterEstimator
  from pgmpy.models import BayesianNetwork
label_desc: Use image node_id 2 for calling the TestParameterEstimator obj's underlying member method code with example usage: obj.test_state_count() without return types