code: def testAssertsNonPositiveSlope(self):
      with self.assertRaisesOpError("`knot_slopes` must be positive"):
          bijector = rational_quadratic_spline.RationalQuadraticSpline(
              bin_widths=[0.1, 0.2, 1],
              bin_heights=[1, 0.2, 0.1],
              knot_slopes=[-0.5, 1],
              validate_args=True,
          )
          self.evaluate(bijector.forward([0.3]))
  
      with self.assertRaisesOpError("`knot_slopes` must be positive"):
          bijector = rational_quadratic_spline.RationalQuadraticSpline(
              bin_widths=[0.1, 0.2, 1],
              bin_heights=[1, 0.2, 0.1],
              knot_slopes=[1, 0.0],
              validate_args=True,
          )
          self.evaluate(bijector.forward([0.3]))
  
imports: import functools
  import hypothesis
  from hypothesis import strategies
  import numpy
  import tensorflow.compat.v2
  from tensorflow_probability.python.bijectors import bijector_test_util
  from tensorflow_probability.python.bijectors import hypothesis_testlib
  from tensorflow_probability.python.bijectors import identity
  from tensorflow_probability.python.bijectors import rational_quadratic_spline
  from tensorflow_probability.python.bijectors import real_nvp
  from tensorflow_probability.python.internal import hypothesis_testlib
  from tensorflow_probability.python.internal import prefer_static
  from tensorflow_probability.python.internal import test_util
  from tensorflow_probability.python.internal import tf_keras
label_desc: Use image node_id 9 for calling the RationalQuadraticSplineTest obj's underlying member method code with example usage: obj.testAssertsNonPositiveSlope() without return types