code: def testPdfAtBoundary(self):
      d = half_normal.HalfNormal(
          scale=[4.0, 6.0, 1.3], validate_args=True
      )
      log_pdf_at_boundary = self.evaluate(d.log_prob(0.0))
      self.assertAllFinite(log_pdf_at_boundary)
  
imports: from absl.testing import parameterized
  import numpy
  from scipy import stats
  import tensorflow.compat.v1
  import tensorflow.compat.v2
  from tensorflow_probability.python.distributions import half_normal
  from tensorflow_probability.python.distributions import kullback_leibler
  from tensorflow_probability.python.internal import test_util
  from tensorflow_probability.python.math import gradient
label_desc: Use image node_id 22 for calling the HalfNormalTest obj's underlying member method code with example usage: obj.testPdfAtBoundary() without return types