code: def testGradientsThroughSample(self, process_name, data):
      tfp_hps.guitar_skip_if_matches(
          "VariationalGaussianProcess", process_name, "b/147770193"
      )
      process = data.draw(
          stochastic_processes(
              process_name=process_name, enable_vars=True
          )
      )
      self.evaluate([var.initializer for var in process.variables])
  
      with tf.GradientTape() as tape:
          sample = process.sample()
      if (
          process.reparameterization_type
          == reparameterization.FULLY_REPARAMETERIZED
      ):
          grads = tape.gradient(sample, process.variables)
          for grad, var in zip(grads, process.variables):
              self.assertIsNotNone(
                  grad,
                  "Grad of sample was `None` for var: {}.".format(var),
              )
  
imports: from absl.testing import parameterized
  import hypothesis
  from hypothesis import strategies
  import numpy
  import six
  import tensorflow.compat.v2
  from tensorflow_probability.python.distributions import gaussian_process
  from tensorflow_probability.python.distributions import gaussian_process_regression_model
  from tensorflow_probability.python.distributions import student_t_process
  from tensorflow_probability.python.distributions import student_t_process_regression_model
  from tensorflow_probability.python.distributions import variational_gaussian_process
  from tensorflow_probability.python.experimental.distributions import marginal_fns
  from tensorflow_probability.python.internal import hypothesis_testlib
  from tensorflow_probability.python.internal import reparameterization
  from tensorflow_probability.python.internal import tensor_util
  from tensorflow_probability.python.internal import tensorshape_util
  from tensorflow_probability.python.internal import test_util
  from tensorflow_probability.python.math.psd_kernels import hypothesis_testlib
label_desc: Use image node_id 3 for calling the StochasticProcessParamsAreVarsTest obj's underlying member method code with example usage: obj.testGradientsThroughSample(process_name, data) without return types