code: def _gaus_dens(mean, var, x):
      """evaluate the gaussian density (mean,var) at points x"""
      Q = -((x - mean) ** 2) / (2 * var)
      return 1.0 / np.sqrt(2 * np.pi * var) * np.exp(Q)
  
imports: import numpy
  import scipy.special
  import scipy.stats
label_desc: Use image node_id 4 for calling a global function with example usage: _gaus_dens(mean, var, x) and returns: unknown