code: def norm_dlldy(y):
      """derivative of log pdf of standard normal with respect to y"""
      return -y
  
file_path: statsmodels/statsmodels/sandbox/regression/tools.py
imports: import numpy
  from scipy import special
  from scipy.special import gammaln
label_desc: Use image node_id 6 for calling a global function with example usage: norm_dlldy(y) and returns: unknown