code: def test_pdf(self):
      cpd1 = LinearGaussianCPD("x", [0.23], 0.56)
      cpd2 = LinearGaussianCPD(
          "y", [0.67, 1, 4.56, 8], 2, ["x1", "x2", "x3"]
      )
      np_test.assert_almost_equal(cpd1.assignment(1), 0.3139868)
      np_test.assert_almost_equal(
          cpd2.assignment(1, 1.2, 2.3, 3.4), 1.076e-162
      )
  
file_path: pgmpy/pgmpy/tests/test_factors/test_continuous/test_Linear_Gaussian_CPD.py
imports: import unittest
  import numpy.testing
  import pandas
  import numpy
  from pgmpy.factors.continuous import LinearGaussianCPD
label_desc: Use image node_id 3 for calling the TestLGCPD obj's underlying member method code with example usage: obj.test_pdf() without return types