code: def testPdfAtBoundary(self):
      low = [1.0, 2.0, 3.0]
      peak = [2.0, 3.0, 4.0]
      high = [3.0, 4.0, 5.0]
      dist = pert.PERT(low, peak, high, validate_args=True)
      pdf = self.evaluate(dist.prob([low, high]))
      log_pdf = self.evaluate(dist.log_prob([low, high]))
      self.assertAllEqual(pdf, np.zeros_like(pdf))
      self.assertAllNegativeInf(log_pdf)
  
imports: import numpy
  from scipy import stats
  import tensorflow.compat.v2
  from tensorflow_probability.python.distributions import pert
  from tensorflow_probability.python.distributions.internal import statistical_testing
  from tensorflow_probability.python.internal import assert_util
  from tensorflow_probability.python.internal import test_util
label_desc: Use image node_id 17 for calling the PERTTest obj's underlying member method code with example usage: obj.testPdfAtBoundary() without return types