code: def aps09_f(x, n):
      r"""Upside down quartic with parametrizable height"""
      return (1 + (1 - n) ** 4) * x - (1 - n * x) ** 4
  
imports: from __future__ import division, print_function, absolute_import
  from random import random
  import numpy
  from scipy.optimize import zeros
label_desc: Use image node_id 37 for calling a global function with example usage: aps09_f(x, n) and returns: unknown