code: def _norm_logpdf(x: np.ndarray) -> np.ndarray:
      return -(x**2) / 2.0 - _norm_pdf_logC
  
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 7 for calling a global function with example usage: _norm_logpdf(x) and returns: unknown