code: def _norm_sf(x):
      return special.ndtr(-x)
  
file_path: statsmodels/statsmodels/distributions/edgeworth.py
imports: import warnings
  import numpy
  from numpy.polynomial.hermite_e import HermiteE
  from scipy.special import factorial
  from scipy.stats import rv_continuous
  import scipy.special
label_desc: Use image node_id 5 for calling a global function with example usage: _norm_sf(x) and returns: special