code: def testValidateArgs(self):
      with self.assertRaisesOpError("must be positive"):
          k = spectral_mixture.SpectralMixture(
              logits=np.ones([7], np.float32),
              locs=np.ones([7, 1], np.float32),
              scales=-np.ones([7, 1], np.float32),
              validate_args=True,
          )
  
          self.evaluate(k.apply([1.0], [1.0]))
  
file_path: probability/tensorflow_probability/python/math/psd_kernels/spectral_mixture_test.py
imports: from absl.testing import parameterized
  import numpy
  import tensorflow.compat.v2
  from tensorflow_probability.python.internal import test_util
  from tensorflow_probability.python.math.psd_kernels import spectral_mixture
label_desc: Use image node_id 4 for calling the SpectralMixtureTest obj's underlying member method code with example usage: obj.testValidateArgs() without return types