code: def testGammaNonPositiveInitializationParamsRaises(self):
      alpha_v = constant_op.constant(0.0, name="alpha")
      beta_v = constant_op.constant(1.0, name="beta")
      with self.assertRaisesOpError("x > 0"):
          gamma = gamma_lib.Gamma(
              concentration=alpha_v, rate=beta_v, validate_args=True
          )
          self.evaluate(gamma.mean())
      alpha_v = constant_op.constant(1.0, name="alpha")
      beta_v = constant_op.constant(0.0, name="beta")
      with self.assertRaisesOpError("x > 0"):
          gamma = gamma_lib.Gamma(
              concentration=alpha_v, rate=beta_v, validate_args=True
          )
          self.evaluate(gamma.mean())
  
imports: import importlib
  import numpy
  from tensorflow.python.eager import backprop
  from tensorflow.python.framework import constant_op
  from tensorflow.python.framework import tensor_shape
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops import math_ops
  from tensorflow.python.ops import nn_ops
  from tensorflow.python.ops.distributions import gamma
  from tensorflow.python.ops.distributions import kullback_leibler
  from tensorflow.python.platform import test
  from tensorflow.python.platform import tf_logging
label_desc: Use image node_id 21 for calling the GammaTest obj's underlying member method code with example usage: obj.testGammaNonPositiveInitializationParamsRaises() without return types