code: def test_discrete_network(self):
      metric = log_likelihood_score(self.model, self.data)
      self.assertTrue(isinstance(metric, float))
  
file_path: pgmpy/pgmpy/tests/test_metrics/test_metrics.py
imports: import unittest
  import pandas
  from sklearn.metrics import accuracy_score, f1_score
  from pgmpy.metrics import correlation_score, log_likelihood_score, structure_score
  from pgmpy.utils import get_example_model
label_desc: Use image node_id 2 for calling the TestLogLikelihoodScore obj's underlying member method code with example usage: obj.test_discrete_network() without return types