code: def testAssertValidSample(self):
      gg = gamma_gamma.GammaGamma(
          concentration=2.0,
          mixing_concentration=0.1,
          mixing_rate=3.0,
          validate_args=True,
      )
      with self.assertRaisesOpError("Sample must be non-negative."):
          self.evaluate(gg.log_prob(-0.1))
  
file_path: probability/tensorflow_probability/python/distributions/gamma_gamma_test.py
imports: import numpy
  import tensorflow.compat.v2
  from tensorflow_probability.python.distributions import gamma_gamma
  from tensorflow_probability.python.internal import test_util
label_desc: Use image node_id 5 for calling the GammaGammaTest obj's underlying member method code with example usage: obj.testAssertValidSample() without return types