code: def fun(self, x):
      E = (
          -20.0 * exp(-0.2 * sqrt(0.5 * (x[0] ** 2 + x[1] ** 2)))
          + 20.0
          + np.e
          - exp(0.5 * (cos(2.0 * pi * x[0]) + cos(2.0 * pi * x[1])))
      )
      return E
  
imports: import time
  import numpy
  from numpy import sin, cos, pi, exp, sqrt, abs
  from scipy.optimize import rosen
label_desc: Use image node_id 1 for calling the Ackley obj's underlying member method code with example usage: obj.fun(x) and returns: E