code: def test_class_init(self):
      phi1 = ContinuousFactor(["x", "y"], self.pdf1)
      self.assertEqual(phi1.scope(), ["x", "y"])
      self.assertEqual(phi1.pdf, self.pdf1)
  
      phi2 = ContinuousFactor(["x1", "x2"], self.pdf2)
      self.assertEqual(phi2.scope(), ["x1", "x2"])
      self.assertEqual(phi2.pdf, self.pdf2)
  
      phi3 = ContinuousFactor(["x", "y", "z"], self.pdf3)
      self.assertEqual(phi3.scope(), ["x", "y", "z"])
      self.assertEqual(phi3.pdf, self.pdf3)
  
imports: import unittest
  import numpy
  import numpy.testing
  from scipy.special import beta
  from scipy.stats import multivariate_normal
  from pgmpy.factors.continuous import ContinuousFactor
label_desc: Use image node_id 4 for calling the TestContinuousFactor obj's underlying member method code with example usage: obj.test_class_init() without return types