code: def li3(z):
      """Polylogarithm for negative integer order -3
  
      Li(-3, z)
      """
      return z * (1 + 4 * z + z**2) / (1 - z) ** 4
  
file_path: statsmodels/statsmodels/distributions/copula/_special.py
imports: import numpy
  from scipy.special import factorial
label_desc: Use image node_id 1 for calling a global function with example usage: li3(z) and returns: unknown