code: def _extract_array(self, kwargs_list):
          
          lens_model = self._lens_mode_list[0]
          if self._solver_type == 'CENTER':
              center_x = kwargs_list[0]['center_x']
              center_y = kwargs_list[0]['center_y']
              x = [center_x, center_y]
          elif self._solver_type == 'ELLIPSE':
              e1 = kwargs_list[0]['e1']
              e2 = kwargs_list[0]['e2']
              x = [e1, e2]
          elif self._solver_type == 'SHAPELETS':
              coeffs = list(kwargs_list[0]['coeffs'])
              [c10, c01] = coeffs[1: 3]
              x = [c10, c01]
          elif self._solver_type == 'THETA_E_PHI':
              theta_E = kwargs_list[0]['theta_E']
              e1 = kwargs_list[1]['e1']
              e2 = kwargs_list[1]['e2']
              phi_ext, gamma_ext = param_util.ellipticity2phi_gamma(e1, e2)
              x = [theta_E, phi_ext]
          else:
              raise ValueError("Solver type %s not supported for 2-point solver!" % self._solver_type)
          return x
docs: inverse of _update_kwargs
          :param kwargs_list:
          :return: