code: def test_add_edge_selfloop(self):
      self.assertRaises(ValueError, self.G.add_edge, "a", "a")
      self.assertRaises(ValueError, self.G.add_edge, 1, 1)
  
imports: import unittest
  import networkx
  import pandas
  import numpy
  from pgmpy.models import NaiveBayes
  from pgmpy.independencies import Independencies
label_desc: Use image node_id 11 for calling the TestBaseModelCreation obj's underlying member method code with example usage: obj.test_add_edge_selfloop() without return types