code: def _log_diff(log_p: np.ndarray, log_q: np.ndarray) -> np.ndarray:
      return log_p + np.log1p(-np.exp(log_q - log_p))
  
imports: import functools
  import math
  import sys
  from typing import Callable
  from typing import Optional
  from typing import Union
  import numpy
  from optuna.samplers._tpe._erf import erf
label_desc: Use image node_id 2 for calling a global function with example usage: _log_diff(log_p, log_q) and returns: unknown