code: def pdf2(self, *args):
      return multivariate_normal.pdf(args, [0, 0], [[1, 0], [0, 1]])
  
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 2 for calling the TestContinuousFactor obj's underlying member method code with example usage: obj.pdf2() and returns: multivariate_normal