code: def testPHMCWithLogUniform(self):
      def target_log_prob_fn(x):
          return -(x**2), ()
  
      phmc_state = prefab.persistent_hamiltonian_monte_carlo_init(
          self._constant(0.0), target_log_prob_fn
      )
      seed = self._make_seed(_test_seed())
      (
          _,
          accepted_phmc_extra,
      ) = prefab.persistent_hamiltonian_monte_carlo_step(
          phmc_state,
          target_log_prob_fn,
          step_size=self._constant(0.1),
          num_integrator_steps=1,
          noise_fraction=self._constant(0.5),
          mh_drift=self._constant(0.1),
          log_uniform=jnp.log(self._constant(0.0)),
          seed=seed,
      )
      (
          _,
          rejected_phmc_extra,
      ) = prefab.persistent_hamiltonian_monte_carlo_step(
          phmc_state,
          target_log_prob_fn,
          step_size=self._constant(0.1),
          num_integrator_steps=1,
          noise_fraction=self._constant(0.5),
          mh_drift=self._constant(0.1),
          log_uniform=0.0,
          seed=seed,
      )
  
      self.assertTrue(accepted_phmc_extra.is_accepted)
      self.assertFalse(rejected_phmc_extra.is_accepted)
  
imports: import functools
  import os
  import jax
  from jax import config
  import numpy
  import tensorflow.compat.v2
  from tensorflow_probability.python.internal import test_util
  from fun_mc import backend
  from fun_mc import fun_mc_lib
  from fun_mc import prefab
  from fun_mc import test_util
  from fun_mc import util_tfp
label_desc: Use image node_id 10 for calling the PrefabTest obj's underlying member method code with example usage: obj.testPHMCWithLogUniform() and returns: unknown,  