code: def penalty(x):  # == 0.0
      x = [xi**2 for xi in x]  # x**2
      return abs(sum(x) - 1)
  
imports: from g03 import objective, bounds, xs, ys
  from mystic.penalty import quadratic_equality
  from mystic.constraints import with_penalty
  from mystic.constraints import as_constraint
label_desc: Use image node_id 1 for calling a global function with example usage: penalty(x) and returns: abs