code: def pdf(self, x):
      return 1 / np.sqrt(2 * np.pi) * np.exp(-(x**2) / 2)
  
file_path: scipy/doc/source/tutorial/stats/plots/hinv_plot.py
imports: import numpy
  from scipy.stats.sampling import NumericalInverseHermite
  from scipy.stats import norm
  from scipy.special import ndtr
  import matplotlib.pyplot
label_desc: Use image node_id 1 for calling the StandardNormal obj's underlying member method code with example usage: obj.pdf(x) and returns: unknown