code: def testNegativeScaleFails(self):
      with self.assertRaisesOpError("Condition x > 0 did not hold"):
          dist = horseshoe.Horseshoe(
              scale=[self.dtype(-5)], validate_args=True, name="G"
          )
          self.evaluate(dist.sample(1, seed=test_util.test_seed()))
  
imports: import numpy
  import scipy.stats
  import tensorflow.compat.v1
  import tensorflow.compat.v2
  from tensorflow_probability.python.distributions import horseshoe
  from tensorflow_probability.python.internal import test_util
  from tensorflow_probability.python.math import gradient
label_desc: Use image node_id 8 for calling the _HorseshoeTest obj's underlying member method code with example usage: obj.testNegativeScaleFails() without return types