class_docstr: Chebyshev polynomial models and functions,
  including specific methods for Tn(z) n=2,4,6,8,16, Equation (27-33) of [2]
  
  NOTE: default is T8(z)
docstr: generates a cost function instance from list of coefficients & evaluation points
docstr_tok: ["generates","a","cost","function","instance","from","list","of","coefficients","&","evaluation","points"]
code: def CostFactory(self, target, pts):
      """generates a cost function instance from list of coefficients & evaluation points"""
      raise NotImplementedError(
          "use Polynomial.CostFactory(targets,pts)"
      )
  
imports: from .abstract_model import AbstractModel
  from numpy import sum
  from numpy import asarray
  from mystic.math import polyeval, poly1d
  from mystic.models._model_helper import chebyshev2coeffs, chebyshev4coeffs, chebyshev6coeffs, chebyshev8coeffs, chebyshev16coeffs
label_desc: Use image node_id 5 for calling the Chebyshev obj's underlying member method code with example usage: obj.CostFactory(target, pts) without return types